Well, the problem I see with an IRC channel would be that you've got to open it seperately. It's like having the Forum on Firefox, GoIO opened on Steam, and then mIRC started to access the GoIO channel. Unless there was a forum or ingame integration. Linking the ingame chat somewhere off game would be great of course, and I suppose it'd greatly increase its activity. With an IRC Channel that would work just wonderful, I suppose. There'd be a need for programming an IRC bot that copies the ingame chat-information to the IRC channel, though.