Wow, Shinobi, that was an excellent demo! Well done. It's like a cross between Tetris and Pipe Mania on the old Super Nintendo, but obviously much better since you used a superior engine. After watching the demo, I find myself urging to play it. I think a backdrop and changes every now and then might be a good idea. Even at this early stage, it looks like a fun game.

EDIT: And thanks for crediting me.