What do you call the falling blocks in Tetris?

[The Ghost of RubangB]

After this thread's been dead for 3 days, here are the results:

1) Tetrads: 2

2) Tetriminoes: 1 (spelled tetrominoes, but I'm counting it)

3) Other: 12 (including 1 for "tets")

4) Blocks: 14