I think you are definitely right about the Bat hunt that is coming in Dark Knight Rises. I was surprised to see Bane as the choice, and I also agree that there will probably be another villain coming in.
I actually hadn't caught the "Selena Kyle" casting. I think what I read had immediately interpreted it as Catwoman. Wouldn't it kind of make sense to have Catwoman in the movie though? She's not really a "super" villain. As for Anne Hathaway for the choice, I don't think we need to worry about her being upstaged by Michelle Pfeiffer. Hathaway is talented in her own right, and look at the Nolan/Ledger joker. On that announcement, weren't you worried he wouldn't stand toe-to-toe with Jack Nicholson?