This is a Bloxeed by Sega.  It is a very fun, Tetris like game.  It is a 1 or 2 player game.  You do the exact same thing as in Tetris with your blocks, but in Bloxeed you have a few twists.  There are little letters in some block shapes and when you remove lines with letters in them, you get limited special items that pause blocks from coming down for you and allow you to clear or add single blocks.  Incredibly fun when playing head to head, allowing you to send your cleared lines over to your challenger's screen.