Eventually most of the advanced search features offered by Google will disappear. Most specialized search engines, most search operators, most filters. They aren't used by many people and Google now focuses on other ways to provide answers.

Google Blog Search is a specialized search engine for blogs that used to be featured in Google's navigation menu. Google no longer links to the service and one of the only ways to use it was to go to blogsearch.google.com. Now Google redirects the URL to the Google homepage.

You can still use this URL: https://www.google.com/?tbm=blg, but this is just a workaround and Google will eventually remove it.



Search Engine Land has incorrectly reported that Google Blog Search is now inside Google News. Actually Google News has a search filter that only shows the blogs from the Google News index. Obviously, not all the blogs are indexed by Google News and Google News only shows results from the past 30 days.

Just like Google News, Google Blog Search started to show small thumbnails next to the search results. The images that illustrate blog posts are sometimes more helpful than the title or the snippet when you're trying to find a relevant result.


Back in 2008, Google launched a new homepage for Blog Search that included the most interesting stories in the blogosphere. Google clustered related posts and used thumbnails to illustrate them. The homepage no longer includes the top blog posts, but one of its features is now available for all blog posts: thumbnails.

{ Thanks, Herin. }

I remember that someone asked Matt Cutts if Google could restrict search results to homepages. He answered that it's a good suggestion, but adding [-inurl:html -inurl:htm] to your query works pretty well.

Now you can restrict Google results to homepages, but only if you're looking for blogs. Google Blog Search has always highlighted a small number of blogs related to your query and now you can find even more blogs by clicking on the "homepages" filter from Google's sidebar. Google's definitions of blogs is vague and it's likely that any site that offers feeds is included in Google Blog Search's index.

"We've updated Google Blogsearch to make it easier to find blogs that match your query, instead of just finding blog posts. The blogs tool on Google search results filters your results so you see only blog posts. We've added a homepages option that shows a full set of blogs related to your query," informs Jeremy Hylton in a Buzz post. Here are some examples: [tesla car], [google], [android].


{ spotted by François Beaufort. }

Vanessa Fox reports that Google's blog search engine changed the way it indexes blog posts. Until now, Google Blog Search only indexed feeds, so the results weren't very good for sites that offered partial feeds. The site started to offer a more comprehensive search by indexing the entire content of the page, including comments, navigation links and blogrolls.

"We have changed the way we index blog posts to include the full content of the page. We've had occasional complaints about the use of the feed content, particularly the problem with partial feeds. The indexing change has improved the results for a lot of queries, both because we have the full content of the page and because we extract links that are missing from the feeds. The downside of this change is that we see more results that match only the blogroll and other parts of the page that are common to all of a blog's posts," explains Jeremy Hylton. He says that the algorithm will be improved to exclude "the content that isn't really part of the post" to make the results more useful.

Here's an example of a comment from a Google OS post indexed by Google Blog Search:


Tip: if you want to find recent blog posts, don't sort the results by date. Just select "last 12 hours" or "last day" from the sidebar. This way, you'll get relevant results and you'll minimize the number of splogs (spam blogs) in the list of search results.

Google Blog Search's homepage has been updated and it now includes a list of popular stories, which are categorized and clustered similarly to Google News.

"Blog Search uses a set of algorithms to try to determine the most popular stories in the blogosphere. We consider factors such as a blog's title and content, as well as its popularity throughout the rest of the blogging community. Then we display groups of posts that are closely related," explains the FAQ.


It seems that Google Blog Search didn't select some authoritative blogs to be listed on the homepage and almost any blog post could be included in a Blog Search cluster. There are 11 categories: politics, US, world, business, technology, video games, science, entertainment, movies, television and sports, but they aren't equally represented.

Google shows a chart for the number of blog posts that discuss a story:


Unfortunately, Google is not able to detect spam posts, plagiarism, forums or blog comments. Google Blog Search doesn't provide yet feeds for the top stories and the search results aren't clustered.


The new Blog Search homepage is a decent alternative to the technology-focused Techmeme and to Technorati's front page. Hopefully, Google will filter the low-quality posts and it will integrate the service with Google News.

{ Thanks, Jonathan. }

Even it still has problems with duplicate content and spam, Google Blog Search has an important advantage over other blog search engines: it actually finds the most important search results. This is the default option for displaying results and it's recommended to use it even if you only want to read fresh news, as you can change the time interval to "last hour" or "last 12 hours".

Google's blog search engine lacks a homepage that displays the most important posts from the blogosphere, but there's a way to find interesting posts without entering a query. For some strange reason, if you search for [label:keyword] or [view:keyword] (keyword can be anything you like), Google ignores your query and displays a list of blog posts. We can assume it's a list of blog posts relevant for any query.


Related:
How Google Blog Search ranks results

Google Blog Search is now a part of your search history. That means every time you use the specialized search engine for blogs and you're logged in, your query is associated with your account and made available in the Google History interface. You can browse the list of queries and find a web page you visited in the past, but only if it was a Google search result. To augment Google History with all the web pages you visit, you need to install Google Toolbar and enable this option.

Even if Google Blog Search doesn't have too many interesting features, I still use it more often than Technorati because it's faster, it's not down for hours, it's much more comprehensive and it has features not available in any other important blog search engine. I still use Technorati for finding backlinks, because Google does a poor job in this area (compare Technorati with Google Blog Search). Unfortunately, Google Blog Search indexes a lot of spam posts that steal content and use it for lucrative purposes.

Google has two features that reduce the number of splogs (spam blogs) from search results. Like in web search, there's a duplicate filter that removes some of the posts that are almost identical. But it doesn't exclude all of them and it doesn't find posts that duplicate articles from news sites like Business Week.


The second feature is the option to sort results by relevancy, which is enabled by default. It may seem counterintuitive to sort blog search results by relevancy and not chronologically, but that's a great way to filter splogs or at least move them at the bottom of Google's search results. Google uses a lot of signals to rank blog posts, including PageRank, the number of feed subscriptions or the amount of duplicate content. But if you sort the results by relevancy, you'll find both recent and old posts and that's not always the optimal solution. A better way is to restrict the results to a recent period of time in the sidebar (to the last day or the last hour, depending on the volume of posts).


If you see a "References" link after the snippet, that's an indication that Google found (a significant number of) backlinks, so the result should be a little more reliable.

Many blogs use Google Alerts to pollute the web and make money, so you could also add [-"google alert"] to your query (a search for "google alert" returns more than 200,000 results). A lot spam blogs are hosted by Google's Blog*Spot, so removing the posts from blogspot.com could increase the quality of your results, but also remove non-spammy blogs like this one or Google's official blogs. I also noticed that many spam blogs use the .info TLD. A recent study showed that, when searching for commercial keywords, 75% of the results from blogspot.com and 68% of the results from .info sites are spam.

It's also a great idea to restrict the result to English (or another language) in "Advanced blog search".

So here's a summary:

1. sort the results by relevancy
2. restrict the results to a recent period (last day)
3. restrict the results to English (or another language)
4. if you really have to sort the results by date, remove the posts that follow a spammy pattern (for example, add -"google alert" -site:blogspot.com -site:.info to your query), but make sure you don't remove important results
5. check the posts that contain "References"

Google should do a better job at detecting spam in Blog Search results and identifying results from sites that happen to have feeds, but they're not blogs. It should also make it more difficult for spammers to use sites like Blogger or Google Alerts to pollute the search results.

Google's blog search engine has a bug that shows weird suggestions for your query in the seventh page of results. While you can't see the weird "did you mean" for every query, I got the message for two different queries.

One of the suggestions was:
"Elena Dementieva" (naked| scandal| divorce| separated| cancel| lawsuit| police| injured)

As you probably know, | is an alternative way of entering the boolean operator OR that triggers all the results which contain at least one of the keywords separated by the operator. But this suggestion is most likely a bug because is completely unrelated to the query and very few people use advanced operators.

Unlike most blog search engines, Google Blog Search ranks the results by relevancy. You can change that by clicking on "sort by date", but the default option is useful if you want to find the most significant blog posts about a topic. But how does Google rank blog posts?

A new patent gives us some answers. Google uses indicators to reflect the quality of a blog or of a blog post.

Positive signals	Negative signals (spam signals)
links from blogrolls (especially from high-quality blogrolls or blogrolls of "trusted bloggers") links from other sources (mail, chats) using tags to categorize a post PageRank the number of feed subscriptions (from feed readers) clicks in search results	posts added at a predictable time different content between the site and the feed the amount of duplicate content using words/n-grams that appear frequently in spam blogs posts that have identical size linking to a single web page a large number of ads the location of ads ("the presence of ads in the recent posts part of a blog")

To rank the search results, Google combines a quality score obtained by mixing those signals with a relevance score (IR score) that depends on the query. "The IR score may be determined based on the number of occurrences of the search terms in the document. The IR score may be determined based on where the search terms occur within the document (e.g., title, content, etc.) or characteristics of the search terms (e.g., font, size, color, etc.). A search term may be weighted differently from another search term when multiple search terms are present. The proximity of the search terms when multiple search terms are present may influence the IR score." (the quote was slightly altered for clarity)

We learned that Google uses all kinds of factors to determine the popularity and the quality of a blog, but that doesn't mean less popular blogs are left out if they have relevant content. You should also try to avoid all the negative signals that may indicate your blog is spammy.

{ via Search Engine Roundtable }

Let's say you upload a video to a site like YouTube and you want to see who viewed your video and where. An important number of views come from other sites that embed your video or link to it. You can use Google Blog Search to find them.

Find links to the video
A YouTube video has an address like: http://www.youtube.com/watch?v=o-KWYYIY4jQ. Paste the address in Google Blog Search and you'll find blogs and forums that link to the video.

Find sites that embed the video
You'll need to look at the code that needs to be added to a site and note the address included there: embed src="ADDRESS". For YouTube, this is a small alteration of the previous address and is similar to: http://www.youtube.com/v/o-KWYYIY4jQ. Now that you have the address of the embeddable Flash object, paste it in Google Blog Search and find a list of blogs.

An easier to find both kinds of blogs is to go to Technorati and to type the address of the video, but this only works for YouTube, while Google's Blog Search works for other sites too.

Google News changed the right sidebar to look more like Blog Search. You'll notice this when you search: instead of the standard navigation links, there are options to change the time interval.

Google News added links to Blog Search in October last year and the integration was successful, even if it was just a small step. Eventually the two search engines should merge, as blogs become more influential and credible.


Related:
More about Google News
A new perspective for Google News

{ Thank you, Dave P. }

The purpose of a blog search engine is to index blogs and to show some information easy to find in a feed, like the date of a post, the author or the tags associated with a post. Unlike web search engines, blog search engines have less sites to crawl and the feeds save them a lot of time, so they pick new posts much faster.

You should use a blog search engine when something important has just happened and you want to find out what people (and not the media) think about it. You can also use them for news that aren't in mainstream and for niche subjects.

I like Technorati's homepage because I can find what's popular right now: the top searches, tags, the most popular content. I like them because they show numbers next to each blog, like number of blogs that link there or the rank of a blog. Their numbers are simply irrelevant because the links aren't equal in importance, but it's nice to have the comfort of a ranking (it's similar to Alexa). Technorati is often down or pretty slow, but they have cool widgets to add to your blog or feed so I forgive them.

Google Blog Search is all about search. Unlike Technorati, Google Blog Search is not down or slow and sorts the search results by relevance. That may seem weird, so you can also sort them by date. Google's search engine is cool because you can easily change the time interval and create mail alerts for your favorite topics. For some queries, you'll also find a lot of spam, mostly from Blogspot.

Ask Blogs & Feeds wants to impress you. Blogs are a domain where Ask.com is strong (they own Bloglines), so their blog search engine must be good, right? Yes, but there are too many options. You can search for posts, feeds and news. You can sort the results by relevance, popularity and time. For each search result, you have the option to subscribe to the feed, send the content to your blog and to preview it right inside the search results page. That's cool, so why should I visit the blog? Ask's strongest point is the preview option and the option to sort posts and feeds by popularity, which uses Bloglines stats.

Sphere is good for only one thing: to find related posts and blogs. So you read something interesting and want some context. Sphere proudly shows you something to read. You can add the "Sphere it" button in your browser and use it when you get lost in a strange article.

Icerocket is a mix of Technorati, Ask and Google Blog Search (in fact, they copied a lot from Google's interface). It's also the best-looking blog search engine, but there's no way to sort the results other than by date or to restrict to a language.

The most original blog search engine is Findory that personalizes the results by analyzing your clicks. It's far less comprehensive than the others, but you'll love the search results recommended just for you. It's a good idea to create an account and to add your favorite blogs.

So if you want to have some idea about a feed and its popularity, try Technorati. If you want good results and a minimalistic interface, go to Google Blog Search. To preview search results, use Ask, and to find related posts, Sphere could help you. Icerocket tries to be a bit of everything, but it only partially succeeds. Findory shows mostly popular blogs, but it's a good filter if you don't want to read too many posts.

It would be nice to have a search engine that sorts the posts by date, but it also takes care to remove irrelevant results (including spam). A blog search engine that clusters the results by topic, like Google News, but also shows the connection between posts and their dependency. A way to monitor what interests you and to filter the good stuff.

I mentioned in November that Google tested an OneBox at the bottom of the search results that lists recent blog posts related to your query. Now the OneBox is live and can be triggered by adding "blog" at the end of your query (for example: search for search blog, music blog, google blog and look at the bottom of the page). You'll also find it for other queries that contain "blog", like Google Groups, as there are a lot of people who talk about the new version of Google Groups.


As Google Blog Search updates much faster than the general index, these results can be found only using a blog search engine. At least for now. Then they'll become a part of Google's main index.

Google offers a lot of OneBox flavors, that enhance the search results by adding results from specialized databases or by providing a direct answer to your query.

Homework:
1. Do you pay attention to OneBox results?
2. If you can't find a good result for your query, do you try specialized search engines (blog search, Google Books etc.)?

Update:

Andy Boyd spotted a new Google OneBox, for blog search, at the bottom of the search result page. The integration seems to be just an experiment and it's visible only to a small number of users.

Google has recently added links to Blog Search in Google News.

Related:
OneBox results

Google News links to Blog Search on the homepage, and lets you go to Blog Search if you want to find more news. Maybe Google could add more features from my list of suggestions, and starts to connect traditional news sources with blogs.