Like it man, I'd only say the forward and backwards movement feels a little odd...also a simple highscore screen would be ace...just the highest score achieved on the game so far :)
In retrospect, the decision to make vertical movement slower than horizontal was weird for a lot of people's tastes. (I did so initially because it seemed that I was bumping into stuff vertically super often. Not very good grounds for such a crazy tweak, I know.) High score tracking is a great suggestion. I allotted myself a very finite amount of time to do this project, so I cut all but the most important bits. Thanks for keeping an open mind, for playing, and for the great feedback! :)