search engine market share?

Is there reliable information describing each search engine's share of the search market?

I heard Google has around 45%, then yahoo follows with around 30% and then MSN has around 20%. Is that roughly correct? Is there any other good info out there?

 

I don't think that's correct. Google has more than 45% of the market.

 

bah, a little more searching and I answered my own question - http://www.webmetricsguru.com/2007/02/january_07_search_market_share.html

Seems it goes like this:
Google - 62%
Yahoo - 23%
MSN - 8.5%
Ask - 3.5%
AOL - 2%

 

those numbers seem correct