Using GAIM for a while. A couple things I noticed. It logs me off without telling me. A number times in middle of a conversation with someone the other side all-of-a-sudden goes silent. I then log off and back on, and they confirm that I was gone for a bit. Also, people have complained why I am not on AIM all day like I used to be. So, I don't know what's going on, but I do know that there's an issue.
Another things is more from a privacy perspective. If I keep a window open to someone, it shows me when the person logs off and on. Not a biggie, just something I noticed. If I'm not at home, I basically get a full report of when some people signed on and off throughout the day.