Seeing the game in action was great, it feels like it's been forever. The Covenant have finally been confirmed as being playable in skirmish mode, though they won't have their own campaign or anything. And Master Chief himself won't be in the game, though he wouldn't really fit. The game aspires to be more about creating an army, not just controlling a single player. Though of course there will be Spartan units, and they have a really cool special ability: they can capture enemy vehicles.