The only suggestion I would have to make to the authors, it would be great if you would add a "send" button to the bottom of the chat window.
A few times I have run in to a problem when I press the enter key and it drops to the next line instead of actually sending the message. (IE & FireFox). It happens on such a rare occasion though its not really a problem.
Suggestion noted & added to feature tracker. We'll try to get a send button in & reproduce the issue you have reported.