Google has finally launched their blog search engine; the beta version is available at both http://blogsearch.google.com and the Google-owned Blogger branded location, but both locations use the same Google blog search engine.

Google has declined to say how many blogs they’ve indexed. Considering the tit-for-tatting Google does with Yahoo! over the relative size of their respective indexes, that tells me Google’s beta blog search engine is not as large as rival Technorati, which claims 17.1 million sites. I expect Google will quickly increase the size of its blog index and you’ll hear soon enough that they have surpassed Technorati’s size.

Technical Note: Google’s blog search engine searches RSS feeds, so it is not a full-text search engine but will index only what it finds in blog feeds. That means that if you’ve configured your feed to only include a snippet of information from each post, that is all that will be available for Google to read. If you want to open up all of your text to Google, and thereby likely increasing the volume of traffic to your blog, I’d suggest reconfiguring your feed to allow all text to be published.

You cannot submit your feed directly to Google, so the best option for getting results in their blog search engine is to use services such as Pingomatic or Pingoat that notify popular pingservers that you’ve got new content because Google does index the pingservers.

Google’s current competition among blog search engines includes the aforementioned Technorati as well as IceRocket, Feedster, and DayPop.

Trend Watching

The best features of blog search engines such as Technorati, DayPop, and IceRocket are their popularity tools where you can see what the blogosphere is currently linking to and discussing. Google’s beta blog search, like their normal search engine, has an advanced search page but no popularity tools. I would imagine that they will be adding those features because their absence makes it far less compelling for users to switch blog search engines.

Google’s entry into the blog search market does ensure that Yahoo! and MSN will be soon to follow with the big three in the market, that will only help to raise the profile of blogs as content and information providers, and thus, for our purposes, marketing vehicles.