I would suppose its because Halo perfected multiplayer, and 5 years after Halo 2 still no one else has been able to even match that in longevity. hell, what other FPS can you turn into a racing game where you only have the guns of the back of the cars to stop the other team from getting the most laps while holding the blue flag on a custom made map with over 16 people? And if you manage to get them out of the car you have to duke it out samurai style with two/three clashing swords? And there is only one gun in the map, the almighty laser, with which takes a fairly accurate shot to control. meanwhile while racing your own team, the other team sets up traps and ambushes along the way that the the other team must constantly avoid with the flag.
GOTY Contestants this year: Dead Space 2, Dark Souls, Tales of Graces f. Everything else can suck it.
