The blue outlines around the pieces are inconsistant. I'd try to get a program with a grid option, and use it, so there'll be no confusion. You can't have borders leaping around and disappearing and reappearing.
The animation you have looks good, but it really seems like you cut it short. I'd really like to see this extended, so that the block drops from higher up, and maybe have more than one block fall.
It's been a while since I've actually played tetris, but I don't think your screen proportions are correct either. I remember the game play area being a lot taller/narrower. It'd also be spiffy if you dressed up the screen with the onion dome theme that was persistent in the original tetris.
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