Nice job on posting these videos. This has been a really helpful forum for me and I'm sure a lot of other people.
I read your other post about your goals for 2013. Here's one big thing: study up on positioning for these lifts. If you're not training with a coach, you'll have to be a coach onto yourself. The good thing is there is a lot of good material out there. I think that if you're resourceful, you'll make improvements quickly.
In order to be able to handle more weight, you're going to have to improve your position when the bar gets to the knee, mid thigh, and hip. Also, you're going to need to improve your positioning in the bottom of the squat. Flexibility and motor patterns are going to be critical.
Greg has some good lifts and drills on this site that you could put into practice. As I watch your videos, two come to mind: the video where the lifter pauses at certain points throughout the pull, and the video of the three position snatch/clean. Both are going to help you with your positioning, strengthen you at certain points throughout the lift, and both are going to help you become explosive.
Good luck reaching your goals. August 2013 is a ways away, so take your time and don't skimp on the technique.
If you can find a coach, do it. You will progress much faster.