7Hells said:
I hope thats not true. I dont want Two-Face to be the climactic villian

And if it isnt Two-face for the third movie what villian could top both Joker and Two-Face?
I think it could be interesting for TDK to not end on a cliffhanger, but just have the story still continue to the third.
I would love to see TDK have the story revolve around the Joker...and then when the third one comes around it has a story more focused on Harvey/Two Face. You could easily have other villains and what-not, but those two characters would be the focus, besides batman/bruce of course.
The third one should (or at least, I'd find it interesting) if it ended something like this:
Batman and Two face have some sort of showdown. After defeating Two Face, Batman manages to bring Harvey back, even if its momentarily. It gives Batman that hope. That feeling he's succeeded somewhat, and then The Joker makes his final appearance. He kills Harvey in front of Batman and manages to escape. The third film could end with the Joker still at large, and Bruce, although devastated still feels there's more he has to do. He knows the Joker will be back, and gotham still needs saving.
I picture a funeral scene at the end, and afterwards Bruce is talking to Alfred. Alfred asks him what he's going to do now, and Bruce responds "Gotham still needs to be protected." Then it shows Batman on a rooftop, the batsignal appears in the air and he shoots the grapple and swings toward the signal.
Of course...it wouldn't be written so lame or sucky. Just what I came up while sitting here.