The Wednesday Book Club has been meeting on the ObservationDeck since we used hashtags to define a forum, if not before. Because the Odeck is affiliated with io9, the group leans more toward science fiction and fantasy.
As far as I'm concerned, the BookClub Kinja was not intended to supplant or compete with the Wednesday Book Club. Because it's part of the ObservationDeck, it is their group, but it is also people talking about books and that's rarely a bad thing. Unless someone objects, I'd to get into the habit of sharing their posts her.