Let's face it, this is absolutely massive news and although rumored for some time it now looks to be confirmed as outlined in the official Microsoft press release below. Finally it looks as though Google might have a serious challenger.
http://www.microsoft.com/presspass/press/2008/feb08/02-01CorpNewsPR.mspx
Post from Fish and Clicks: The Affiliate Marketing Blog.
Microsoft to buy Yahoo for $44.6 Billion