Allow me to begin by apologizing for dropping the ball. It is apparent that there is a lot of interest in this topic, so I am going to propose a format for our book club.
Traditional book clubs involve having members reading a certain portion of a book, them meet to discuss questions--often determined by a moderator/facilitator--that pertain to the reading. Whereas it would be possible to do that an various websites (I'm not sure which ones allow group chats, though!), another option would be to have the moderator post question at the beginning of the assigned reading, then have members e-mail their comments.
This would be a good analog to the "real" book clubs you find at libraries and bookstores. For example, a Book Club member could e-mail his ore her comment in response to the posted questions (and even raise his ore her own questions). Group members would comment in response, and that would lead to further dialog and exploration.
Personally, I think it is valuable to have the facilitator be a rotating position, available to any member who volunteers for it. I suggest that the facilitator be allowed to choose the next book for the group to explore. As far as question to ask, if you go to a Book Club at library (I've never been to one, but I did look at a "Book Club bag, which includes about 10 copies of a book, plus suggestions for topics to explore in each section of the book.
I am going to anoint myself as the initial facilitator, and I am going to choose the first book: Head Cases, by Michael Paul Mason. I know that several members of the TBI Book Club have already read it; if you have, you are free to abstain from this conversation; on the other hand, your insights are no less valuable for having read the book already.