Memoirs of a Geisha- the movie

Maybe I'm just an uber-nerd, but I can't wait till this movie comes out. If the movie is half as good as the book... For anyone who hasn't read the book, I highly recommend it (if it's your sort of thing). I don't get why they've got Zhang Zhiyi (Chinese) and Michelle Yeoh (Malaysian) cast to play a Japanese women. It's a little silly, really. Doesn't that just reinforce the stereotype that "all Asians look alike?" Something this Asian ponders....