This game is addicting, even if Tetris has advanced a lot in 30 years! I'm sorely missing things like hard drops, holds, ghost pieces, and not having to press left or right every time I want to move a space.
I can't find any flaws in your recreation, but this is really not a great version of Tetris! However, those medals do have me coming back again and again. The Newgrounds API screen pops up every time I restart the game, which is pretty annoying. If you can fix that I would happily give a full 5 stars.
Now if you'll excuse me, I'm off to play a more modern version of this game!