I like and often use the chat function of FaceBook that was incorporated as part of their new features in replacing the old FaceBook layout; the only thing that I don't like about the feature; is that it's not stable (imagine the frustration of finding out that your friends have somehow gotten "disconnected" when you're in the middle of a conversation) seeing how FaceBook and how browsers work, the solution would be to have the chat in a separate browser window.
