There's probably changes to the Yahoo! thingy. I think they've changed the protocol a bit too because Plus! is doing the 1s and 32s again for names
EDIT: 200th post
EDIT 2: On the Live page one of the features (I think Yahoo! related) said "Coming Soon" before. I forget which though...now it's not there
update: that was just the yahoo integration
EDIT 3: Found some changes.
Change 1: The "Read the Messenger Team Blog" menu item in Help now goes to the spaces.live.com domain instead of the spaces.msn.com domain.
Change 2: There seems to be another link for dynamic content in the Display Picture changer window, and BlueMountain's link has been renamed to Kiwee.
Change 3: The "More" button in the winks panel is now a menu leading to different content providers.