Oh please, spare us the Riddler! I remember saying to my friend after The Dark Knight came out that they could successfully make 4, 5, maybe 7 of these movies, but if they're going to insist on picking the stupid, well known villains, I'd almost rather TDK be the last Batman movie. Why can't they just pick some better, not well known villains from the comics? I know they've got everything from pyromaniacs to lizard men, so let's choose from that pool please.
P.S. Jon Depp is a great actor, but I'm reluctant to allow more big name celebrities into the franchise. It could become a gimmicky trend.