Over the last few months Stephen Law led a 'group read' of Dawkins' God Delusion, which I think worked out fairly well, although I didn't comment as much as I might have done as he was fairly restrictive in what he wanted to cover. I'm inclined to do something similar here, as I think there is a good crowd of people from all over the spectrum of belief and unbelief.
The book I'm going to begin with is Rodney Stark's "The Victory of Reason". I'll write a chapter summary at the beginning of each week and try and kick off some vigorous and fruitful discussion.
I'll begin in January - which should give anyone who wants to join in time to get hold of the book.