I'm thrilled they're using John Williams original theme in the movie. While I was pleasantly surprised with the Batman Begins score it would have been nice to hear Elfman's main theme a few times in the film. I can't wait for next June!
If he didn't use the Williams theme, fans would boycott the movie. Singer compared it to making a Star Wars movie without the theme. He even said the opening credits would be "similar" to the Donner movies.