You have a point Zanker, but I think at the very least Half-Life 2 + Episodes out of the FPS games deserves to be on any list of classics. The storyline is the best I've found outside of RPGs and is well integrated into the gameplay. There's great variation in atmosphere, setting, gameplay all the way through, and as for revolutionary features, look no further than the Gravity Gun/Physics engine,/Garrys Mod. It's very rare that I play an online FPS (Deathmatch) where I spend more time building impeneterable fortresses than actually murderizing people. And yes, it's definitely replayable.
lol, console wars. My ps3 and xbox get along just fine on the same shelf, though the amount of attention they receive from my side is rather disproportionate, but I refuse to state in which side so as not to appear to be taking a side in this trollery. Seriously, we get it, you either can't afford or are too cheap to buy both/all consoles, and have an urge to justify your decision. Don't. (ps3 has no games! xbox has no japanese games! RROD! backwards compatibility! et cetera, ad infinitum.)