Good advice from Derek. My $.02 would simply be to stay on your heels longer. It looks like you're getting up on your toes before the weight has even passed your knees, instead of when you're approaching full extension. Think about that while you're lifting, and that may be enough to get your weight shifted back a bit.
I think I may post this as a disclaimer to any advice given concerning o-lifting technique given on the internet by myself. First, correct the simple things, like start positions. Then, take one piece of advice you get, and work on that. Don't take everything people are telling you to do, and trying all of it at once. Take something that makes sense in your head, drill it like crazy, take another video, and post again.