The question may sound slightly absurd since there are millions of splogs, fake web blog sites consisting of stolen or nonsensical designed solely to drive up traffic numbers of disreputable sites, doing their best to grab attention on the Web. Blog search engine companies don't deny that, but argue that what's most important is keeping them out of search results.

The issue is that if enough spam blogs continue to pollute searches for things like Caribbean vacations, iPods and mortgage insurance, search engine users will become dissatisfied with search engines and stop using them. Advertisers may also question the value of the audiences viewing their contextual pay-per-click ads. On that, both Internet researchers and search engine companies agree.

Currently, at least one-fifth of the blogs that turn up in search results are spam blogs, researchers say.

"The important thing is, yes, there's a large volume of spam blogs that exist, updating themselves and being created," says Adam Hertz, VP of engineering at search engine Technorati. "However, because of the work we're doing the [negative] impact on the user experience and the quality of our data in general is being minimized."

An entire subsystem of Technorati's infrastructure is dedicated to weeding out splogs, which use a large numbers of links to artificially boost their PageRank on different search engines. Splogs usually also contain keyword-based advertising, from Google's AdSense and other programs, that generate a small commission, usually a fraction of a dollar, for every click.

"We have to spend engineering cycles on this stuff when we could be using them to make our services better," Hertz says. "It's a cost to us no doubt." Concerned about the quality of search results, Technorati initiated summit meetings with the industry's heavy hitters - Google, Yahoo, Microsoft, AOL - and Six Apart Ltd., maker of the Movable Type publishing platform and the TypePad hosted blogging service.

Hertz doesn't blame consumers who get annoyed when a search turns up junk, but he believes eventually they'll learn to live with it, just like they do with spam-riddled email.

"I don't think anyone would stop using Google because they saw spam, but they might have to train themselves to do more persnickety searches so they don't get spam," he says.