Splogs, or Interest Search Phobia

Gentlemen, but will someone tell me - does anyone keep statistics on the share of splogs in the total mass of blogs, within Runet or generally around the world?

I did a few searches here by interest, and got a little overwhelmed. On Blog.ru, if you select a search for any popular interest (tag)

blog.ru/people/interests <- add interest to the link, for example, "life"

in response to falling out mainly a stream of porn-splogs with rare intersperses of human blogs. So it became interesting to me, does anyone keep statistics of this misfortune?