Interesting concept. The art for the blocks is very pretty, albeit a little distracting. The palette is nice! It's quite fun moving about the terrain you've created.
The audio is imbalanced. The music is very quiet and the flashing TETRIS light sound is a good deal louder than the other sounds.
I think there should be a buffer between each "down press" for each block, so it's harder to just slam half a dozen blocks in the center.
Good work!