This game is gorgeous. I really enjoyed how you managed to render what looks like a square-shaped physics object in a lower resolution without any blurring, I'd have no idea how to do that.
I feel like making gravity accelerate you a little faster might improve things by making this a little snappier, but admittedly looking at my game I may just be a little too into uber-fast games in general.
Also, it seems as though the music doesn't loop properly, which is something I'm sure you're already aware of.
Nice job!