A book club is a great idea. For purposes of discussion, one book a week is better - I can see having a good discussion for a week, and any longer it might get stale. But some members might have trouble managing one a week. The great thing about a book club, instead of just having a books section, is that it ensures everyone has read the given book. Maybe we could do one a week, but vary the length of the books to make it possible, eg a sub-200 page book on weeks 1 and 3, and a longer one on weeks 2 and 4.
Getting books in the public domain or ones easily torrented would also increase uptake dramatically.