iChat was one of those programs I just never thought I would like, and never gave it ago. The main problem was that no one used AIM, Jabber or dotMac (now mobile me). While Skyping Peppery thought he would try to out iChat, since we were both using OS X. Once you open the ports, iChat is a fairly sexy IM client.
Screen sharing is amazing to use, and you can switch between your screen and the host easily. The only problem I find with it is that there is no copy and paste.
Webcam chat is fairly good, however it does rape the CPU. The effects worked pretty good for me, but Peppery just had problems everywhere when it came to the backdrops.
In general iChat is amazing to use and fun. However the limited support for clients and the dual buddy list kinda of ruins it. I just need more jabber friends I guess. I once spent over 3 months without MSN which was really nice.
Happy new year.