^Emily Blunt just talked about that in a recent interview and said she was flattered by the rumor but it had no validity. She did make a claim that she would love to play Catwoman if there was an offer, however she admitted it would be hard to top Michelle Pfiefer's performance.
http://www.batman-on-film.com/BATMAN-3_rumor_emily-blunt-show-me-the-catwoman_April-9-2010.html
Anyway, as for Nolan finding villains to top The Joker, I think there are plenty. You have to realize that Nolan never really goes for a singular leading villain. With both
Batman Begins and
The Dark Knight he had a main villain (i.e. Ra's al Ghul & The Joker) but they were supplemented by supporting villains like The Scarecrow, Two-Face, Carmine Falcone & Salvatore Maroni. In fact, when you dissect it, each of his films had three big villains -- one representing the main villain element (i.e. the "freak"), one representing the secondary villainous element (i.e. Two-Face was the emotional backbone of
The Dark Knight) and then one representing the mob element (Falcone & Maroni). So one would assume if Nolan intends to follow that pattern that we'll see the same structure in the next
Batman film.
The Riddler probably wouldn't be enough to support an entire film as the villain, at least not after
Batman Forever, but if he's supplemented by Catwoman and The Penguin, then that makes sense. However, there has been slight talk of Nolan creating a new villain (whether main or minor) for the third film, but personally, I would like to see Nolan come up with villains we haven't seen yet. Nolan has denounced The Penguin, saying he doesn't fit within his "realistic" approach for some reason, but what about Black Mask taking up the reigns in the fractured mob factions in wake of
The Dark Knight? I'd love to see Deadshot, who played a role in the
Batman Begins/
The Dark Knight tie-in
Gotham Knight, co-penned by David Goyer. Nolan mentioned at one point that he could be a possibility for the third film. Even though this is a purely unconventional choice, I'd love to see Hugo Strange as a FBI criminal profiler brought in to take down Batman now that he is a vigilante and on the run. So there are many possibilities for villains. I don't think one should be concerned about "topping" The Joker -- because you can't -- but instead focus on a good, strong story and allow the characters to play roles based on that story. Ignoring that and worrying about which villain can top the last one is the same type of poor storytelling that ruined the Burton/Schumacher
Batman films.
