Hmmmm.....well, I think casting is fun and everything, so I'll do it anyway, but logically, DKR would (if it was made) come out after Nolan's series is finished, which will take a few a years. So some of our cast choices might end up looking alot older, hell, some of them might die by then. Eastwood looks like he might snap in half. You might change your mind about some cast members by then. It would be awesome as the last Batman movie made, as kind of like a last hoorah. Anyway, I've got a few, and I'll try to think of more later:
Bruce/Batman: ???
Joker: Christopher Walken or David Bowie (Don't know much about Bowie as an actor, but that pic someone posted before looks ALOT like DKR Joker)
Harvey Dent: Bruce Willis
Gordon: Gotta stick with Clint Eastwood or Paul Newman.
Carrie Kelly/Robin: ???
Mutant Leader: Vin Diesel so far, I mean he looks the part, but I don't really think he could capture the character. I mean, that scene with the Mutant Leader in the jail cell with the cop, asking him about his kids? Creepy. Diesels.....not creepy. So still thinking about that one, but like I said, he does look the part.
SEAN CONNERY WOULD BE A KICK ASS GREEN ARROW
And that's all I got so far.