5. Gears of War 3 – Xbox 360
While the excitement surrounding the Gears of War series has lessened somewhat in the last year, it'll only take a stunning gameplay video or Cliff Bleszinski writing something on Twitter for the internet to be set ablaze. What we've already seen looks amazing, and hopefully the third game in the series will ship with a fully functioning bug-free multiplayer mode. Unless Microsoft reveals something big for 2011, this will easily serve as the Xbox 360's biggest exclusive of the year.