As if you didn't know, The Joker is the main villain in the upcoming Batman Begins sequel: The Dark Knight. :-)
Anyway, there's a VERY fuzzy image of Heath Ledger as The Joker at the link at the end of this post. It's very hard to make out but it looks like Chris Nolan (the director) is in fact going with a white face/green hair look. Now keep in mind the image is from a distance and quite out of focus so it's hard to tell if there is any scarring or anything like that going on in the makeup.
Of course that's interesting news, but what I found pretty creepy were the four "heads" being carried by folks with various incarnations of creepy Joker-looking faces. I managed to clean up the image quite a bit and you can see it by clicking on the small image above.
Source: Superherohype (click for more images)