Rythm
I've never played a game like this before. It's original and very nice, and the controls are simple and good. The music, which is the important factor on the game, is nice too, and somehow relaxing.
I needed to follow the rythm of the song a bit to predict the length of the bars so I could jump without falling and losing a heart, which if is something on purpose or not, still I liked that.
Nice job!