Hold the phone! Or some other cliche describing a need to pause for a moment and reflect. The latest rumours coming from the Batman Begins sequel camp is that some big names are being talked about. According to Moviehole, via Cinematical, Johnny Depp is director Christopher Nolan's top choice for The Joker, and Rachel Weisz would play a Femme-fatale character (who I believe may be Harley Quinn) out for revenge against Batman. WHile the source doesn't mention any names specifically, the clues given are very clear.
Good call...