While I'm not exactly a fan of the idea of bringing Catwoman into this mix, it does seem like a fairly logical step. If I remember correctly, handmaiden_yane made a comment sometime in the past (in my review of Dark Knight, maybe?) that Catwoman should be a villain in the next movie. She called it and I didn't, I'll give her that.
Tom Hardy (who was in Nolan's Inception) has been cast as Bane. Should be interesting to see how Nolan brings that character to the screen, although I think we're getting to villain overload, a small part of what killed the Burton-era Batman movies.
Hey, I'm willing to wait and see. :)