The chat is for community managers (and people who hate community managers, except not really). It's still in its growing stages, but in its fourth week, 126 people contributed.
I'm learning a lot and I think contributing some useful information as well . It takes a fair bit of concentration to keep on track and to keep up, but ultimately it's definitely worth the hour each week.
Do you have any other Twitter chats worth mentioning, or that I should join in?