Tennant plays Peter Vincent, role that was originally played by Roddy McDowall in the original movie. //Film has some information on the role:
We know that David Tennant from Dr. Who is playing Peter Vincent, the showman and pseudo-expert on vampires that Charlie recruits to help fight Jerry. The character has a smaller role here than in the original, but there’s an interesting possibility in the script that could lead to Tennant fans getting a pretty neat performance out of him. I’m not sure if that angle is going to be treated as the script suggests it should.[//Film]
I'm rather sad to hear that the role will be less substantial in the remake than it was in the original. However, I'm sure David Tennant will be splendid in it.
The movie will be in 3D and is set to be released on October 7, 2011