deadsea - 12:30 pm on May 12, 2011 (gmt 0)
I optimize for Google, and despite some threads here recently, Bing and Yahoo don't respond as well to my optimizations. One of my large sites gets 93% of its search engine traffic from Google. Another gets 80% of its search engine traffic from Google.
The second site according to Google analytics:
msn 4.7 %
Not sure how analytics still sees msn as active.