I liked your idea, but I couldn't do it - I was pressing an arrow key every time I heard the beat, but I think there might be a delay between playing the sound and hearing the sound which makes the game go out of sync. Perhaps you could extend the time the player has to move? Eventually I ended up just continuously pressing the arrow key and the character would move every now and again.
I also found the flashing lights distracting, but it might be helpful in some cases. Perhaps include an option to turn it off.
(I can't comment on your game on your page, because the purple on black comments makes the text too hard to see.)