Call of Duty.
If the yearly sales of this juggernaut annual franchise is any indication, you've probably played at least one game in the series. If not, you've probably read about it here on GamePolitics. It breaks sales records. It courts controversy with levels like Modern Warefare 2's "No Russian" where you can gun down an airport terminal full of civilians. Think pieces are written about how it reflects on the games industry from a multitude of different perspectives from gameplay to political ideology.