Gears of War 2 featured a campaign you could blast through over the course of a weekend. The perfect length for the kind of story that strings together a bunch of setpiece spectacles that won't tax your thinking muscles. At one point you end up inside a giant worm and have to fight your way out. It's great.
But it's one of a couple of Gears of Wars that never made it to PC. Maybe because Cliff Bleszinski was going through a "down with piracy phase" at the time, saying things like, "the person who is savvy enough to want to have a good PC to upgrade their video card, is a person who is savvy enough to know bit torrent to know all the elements so they can pirate software."