As Billi said, next month's genre and previous selections are in the first post of this thread (and yep, we started not that long ago really, mid-2011). I can see how it could be easily missed at the present though because I'm in the (slow) process of updating and reformatting the post, so it's a bit messy right now. I should have it all sorted out by say mid-year at the latest.
About restrictions for the Lit Club, the main criteria is that it just be literary and fit the monthly category, and that's about it. For the most part it's left up to the nomination/voting process to weed out any nominations that might not fit well, but sometimes (rarely) I might step in if something definitely doesn't fit.
Hope that helps!