According to Nintendo the new magic in Tetris, squeeze into the tried-and-true formula is, the just revealed Touch Mode.

"Touch Mode is [a] unique take on Tetris [that] really shows off the touch-screen capability of Nintendo DS. Players use a stylus to drag and move Tetriminos in a giant stack to make them fall into horizontal lines. In early levels, they can tap Tetriminos to spin them just the way they need them. Players have as much time as they need to carefully plan their moves, so it plays very differently from the other frantic modes."