I was at the book store yesterday and by chance found the novelization. It is actually written by George Lucas himself, and I must say, he is a pretty good writter. I hope he writes more science fiction novels in the future, I am really enjoying it. Anyway, it has a few things that are not in the movie. It even mentions what species Darth Vader is! He is of some race called Sith, it doesn't say what they are like though. I am betting reptilian.