Simple graphics and sound - I like that. However I really did not like how difficult this was. The difficulty curve was just insane, so if that's what you were going for - nice job! You made the next rage-inducing game. Not only that, but it's way simpler than other rage inducing games!
Going to have to agree with Kinos141 though - putting in the spacebar to jump would be nice.
-Azulles