Oh and to be a bit more on-topic: FPS games are amazing on PC but CoD.... dunno. There are so many more game styles with fps out there.
(in no order, here are some of my fav fps games)
====================
Unreal Tournament (+2004)
Doom 3.
Half Life 1 & 2 (probably best games of all time)
BioShock (not toally an FPS)
Bioshock Inifinite
MassEffect 3 (especially the multiplayer, very intense )
Fallout 3
Crysis (obviously
)
Battlefield (especially 1942)
Return to Castle Wolfenstien
Far Cry
Medal of Honor
Deus Ex (only contender for best game against Half-Life)
FEAR
STALKER SoC (amazing game, probably cheap on steam too)
Quake 3
Portal (not a shooter, but a
must buy)
CoD is great for what it is but PC FPS gaming is much more than CoD
Grab yourself a copy of the Orange box from steam though if you can. Half Life 1, 2, EP 1, Ep 2, and Portal for like $20.
Highest and Lowest Scoring Games - Metacritic
OK, time for me to get to the test chamber.