It took Microsoft and Yahoo a little while to get all of the kinks worked out but they have done it! Windows Live Messenger (WLM) and Yahoo Messenger users can now talk to each other without the need for separate chat clients. Currently this is only compatible with the Beta version of Yahoo Messenger with Voice which means WLM users may not be able to chat with all their Yahoo friends quite yet.
So what does this mean for other companies like AOL and Google? I don’t think people will actually flock to the new WLM or Yahoo Messenger just because of the interoperability but I think it is just more of a convenience for people who currently use both of those messengers. Now they can just pick their favorite and use it.