Interoperability between Windows Live Messenger and Yahoo! Messenger is now live!
Posted by Aj Collins on July 13, 2006
Microsoft and Yahoo have enabled interoperability between there two messengers. No downloads are needed! (unless you don’t have the newer versions of the messengers) You do how ever have to sign up for the beta from Microsoft and Yahoo!. After you sign up all you have to do is restart your messenger!
Here is a test that I did….

Links:
Sign up for Live Messenger to Yahoo! Messenger interoperability
Sign up for Yahoo! Messenger to Live Messenger interoperability
Microsoft press release
Inside WLM blog post







