Quantum Theory
Take the laziest possible copy of Gears of War, then add the terrible aiming mechanics of Kane & Lynch, remove now-common features like blind-firing from cover (!?), add a completely meaningless melee-combo system, and put a shockingly uninteresting level design around it. That's Quantum Theory.
It's hard to believe how a reasonably professional publisher can, in all seriousness, release a game in 2010 that's nothing more than a bad facsimile of a game from 2007.
Progress: Gave Up -- Finished the demo