This is just an idea and by no means a rumor or anything that I've heard. It just seems to me that Nolan has a history of using actors repeatedly in his movies. So I'm looking at the cast of "Inception" and only two actors really stand out as possible characters in a Batman film. They are, of course, Leonardo DiCaprio
and Joseph Gordon-Levitt
The first question is can either one pull off the Riddler? I would go with Levitt due to looks and physique.
The second is: if not the Riddler, which other rogues could these two pull off? DiCaprio is a superior and versatile actor. Levitt I feel has much potential ahead of him. So with that said... DISCUSS!