I know this is a long ways off, and probably 100% inaccurate, but just to generate some discussion:

Batman 3 villian rumors.
http://movies.ign.com/articles/895/895689p1.html

Definately need someone British to play the role of the Penguin, if they decide to use him as the villian, I hope they don't screw him up as bad as they did with Batman Returns.

Depp as the Joker... I guess it could work... he is a bit too mainstream for my taste though... it would suck to basically get Capt. Jack Sparrow in Joker clothing.