Often, as I write my articles, I search weblogs -- the popular online journals that allow just about anyone (including me) to have a voice on the Web. Because bloggers are fairly quick in posting their thoughts, their blogs provide a good way to get a sense of the buzz on a hot topic.

Meanwhile, I also use Google (NASDAQ:GOOG) a lot in my research. And with Google being the king of search, wouldn't it make sense for the service to have a blog-searching function? Google apparently thinks so. It announced this week that it's releasing a beta version a service that you can try right now at blogsearch.google.com. As you'll see, it's done in classic Google style: The interface is simple (a search box and a just a couple of buttons), and the search results are lightning fast.

Google's blog service allows for searches based on relevance and date. Of course, Google has not disclosed the basis of its relevancy system -- it's a trade secret. But that's fine. I prefer using the date as the basis of a blog search, anyway, since I'm mostly interested in the latest thoughts and ideas on a given topic.

There are advanced search features as well. For example, you can search based on date ranges, language, authors, and blog titles. Another cool feature is that you can set up a feed based on your blog-search criteria. Suppose you want to see the latest blog posts on, say, Microsoft (NASDAQ:MSFT). Google will send updates to the RSS or Atom reader you use to collect content.

Interestingly enough, I used the Google blog-search service to get a sense of the buzz on the new product. I found that there are a variety of criticisms: The Google service indexes blogs only back to March 2005 and does not seem to effectively weed out spam blog posts.

But as is the case with other Google services, the company's smart programmers will continue to improve the functionality. Upcoming competition from Yahoo! (NASDAQ:YHOO) and Microsoft, both of which are supposed to launch their own blog-search services soon, should only encourage Google to refine its service.

This is bad news for pure-play blog-search companies, such as Technorati, but it's very good for people like me who increasingly rely on the value of blog content.

However, keep in mind that blog search is a niche. While it is impossible to estimate the size of the market, given that all of the other current players are private companies, the fact remains that traffic to blog-search sites is relatively small. The big gorilla in the space is still Technorati, and even it attracts fewer than 700,000 unique visitors per month.

But in the search-engine race, companies like Google, Yahoo!, and Microsoft need to constantly add new features. Blog search is yet another example of this trend. But, for the most part, don't expect it to have an immediate impact on the bottom line for these companies.

Fool contributor Tom Taulli does not own shares of companies mentioned in this article, but he does have his own blog at www.taulli.com.