We're a little later than our competitor sites getting this one out, but X-Box365 is reporting that they have received unconfirmed reports that Halo may be advertised (as part of some X-Box promotions) during the SuperBowl!
The second commercial pushes a lot of Promo for Halo but I don't have the details on that one yet. I'm told they do half of it as if the viewer was actually in the game and looking around at the action around. Stuff crashing and blowing up all around - characters talking to you and getting shot etc.
Those of you who are in their ancient later 20s like myself will probably remember how much mileage Apple got out of its 1984 commercial at Superbowl '84, which played upon George Orwell's horrific vision of a future, mentally-controlled society. Pretty neat that XBox365 remembers this as well, in an earlier post about possible X-Box Superbowl commercials.