I've come to the conclusion that tablets aren't for serious gaming. Input via touchscreen is really limited compared to a mouse/keyboard setup. Touchscreens excel at newer types of touch-enabled mini games like Angry Birds and Cut the Rope, but that market is already claimed.
i agree with some of you here. it would need to have a set of controls on the body or bluetooth capable. the screen could be touch, but mostly for naving the options and selecting games.... hell maybe even setting waypoints on in-game maps.