OK, maybe it's not quite gab, but OCC does have a new chat room. It might be old technology but it's easy to use and it works!
All you need to know to get started is in the OCC Chat Room forum thread. There you'll find a link to the client and instructions on how to join. Already have your favorite IRC client software? There's also server and channel information in the thread as well.
Come join your fellow OCC members and chat about whatever's on your mind. Just please be courteous, respectful and remember the forum rules also apply to our chat room. So what are you waiting on? See you in the chat room!