This game has two flaws.
1. The TAB key is not an effective key to use in any game. Consider moving each of the controls for Player 1, except the Space bar, one key left for each.
2. The use of j-pop in your Flash makes me hope for a j-pop invasion someday...no wait, that isn't a flaw.
But this Flash seems like some sort of Tetris Attack meets DDR style of game, and has numerous characters to choose. 1337