Rick has made statements that he wanted to expand on the shoutbox in the future, so I think it's completely possible...
If you want a good, low resource chat, there is the jIRC Chat addon at ubbdev, or if you're looking for a non-free/non-irc service, theres the raidersoft chat addon and the FlashChat addon also available at ubbdev (well flashchat is available at tufat.com but the notes from me on getting portions to work are at ubbdev)
