If you played and loved Metal Arms: Glitch in the System for the Gamecube, Xbox, and Playstation 2, then this is the Starcraft scenario for you. If you didn't play the console game, then play this game anyways! (Then go to your nearest game retailer and buy the console game).
The udpate features a choice between an hour long game and a half-hour long game. New units have also been added, and many things have been fixed.