Just built a tank and Warthog batallion (sp?) on Blood Gulch and dominated. Granted 1v1, but still, hella fun. Only additions to demo: lots more maps, up to 3v3 AI/Online Multiplayer, UNSC Leaders have special units, special ugrades/starters, and a powerful unit. Same with covenants on special units. IE: Forge has the Grizzly Mechs instead of Elephants, forget his power unit, but all your supply depots are automatically heavy supply depots on building. Other little things, but i'll save em for when you get the game.