Manaco
several people brought this feature suggestion up already;
the ability to have "tabs" or the ability to be in more than one room at once. I like being in the lobby to chat with random players while being in my alliance room(s) to discuss with my people.
I think if this specific feature was implemented, the chat room itself would be exponentially more useful, and thus may be used more.
I agree that tabbed chat would be a nice addition.
Depending on how much of a drag it would be on the system, a 24-hour chat log would be nice, in order to let people log in and log out of the site while continuing a [very slow] conversation through the chat widget. The alliance boards probably cover this, but an message of the day (MotD) or opening statement feature that could be set by the alliance leader might be nice, if unnecessary.
Overall I really rather like it as it is though. Nice job!