Entertaining!
I have always enjoyed Tetris, and this is a worthy adaptation of the old classic.
Some pointers I have, though:
There is an issue with the yellow block that moves it horizontally when rotated, and that tends to create some issues with last second rotation. Please fix it!
For people who play Tetris for long periods of time, the music might get a bit old, so it would be really great to have a couple of different pieces playing in the background (preferrably a remix of an original Tetris theme, just for the nostalgic value).
It takes a lot of time to get used to using the up arrow key for rotation and having no reverse rotation (especially if you assume the reverse rotation is the down arrow key and find your blocks dropping like flies instead of turning).