Yahoo! Messenger latest beta can now be downloaded at http://beta.messenger.yahoo.com. The big thing about this beta is its voice calling capabilty that lets you have voice IM with other users anywhere around the world for free and
drag-and-drop photo and file sharing
Yahoo have been doing a lot with its IM client and it has a lot more feature then I was aware off. It has definitely moved beyond being just for instant messages which is both good and bad (I like small and focus apps^^), but definitely worth a look and to play around with.