Some odds and ends of suggested links you might like to have a look at:
ONLINE BOOK CLUBS
4MA (4 Mystery Addicts)
Charter: Be clueless no more! Join your fellow bookaholics and discover new authors, great books, and the latest in mystery happenings.
Every month we have a formal discussion of two books selected by the group plus one book in an ongoing series, as well as daily discussions of what we are reading and what's happening in Mystery Land.
Our mystery expertise ranges from very little to quite a lot, but it doesn't matter since everyone enjoys all things mysterious.
Comments (for what that's worth!): The best online book discussion group that I've ever found. Members are widely read, there are lots of structured reading activities and it's basically all about the books. Highish traffic (numbers of emails at times). Just set up some filters and read at your leisure. Nothing is mandatory, very friendly group.
Charter: This is an online Reading Club that caters to the Mystery, Thriller and Horror Book Genres. We feature many Buddy Reads, so please visit the database section for a full schedule.
Comments (for what that's worth!): Lower traffic list - specialises in buddy (small group simultaneous reading of books). Has structured activities as well (nothing is mandatory) - very friendly group.