I looked at the English Wikipedia page about Tetris, and there you can find some images directly from some games. These images have a tetris board with the following sizes (visual, without hidden counting):
1986 IBM PC Version: 10x20
TETYAIS: Soviet game of the mind: 10x20
Official NES Version: 10x20
Tetris (iPod): 10x20
I think it is very easy to see which size is mostly common. But if your board does not fill the free space, just enter a few more lines.
user507580 Nov 14 '10 at 20:18 2010-11-14 20:18
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