I must admit: There aren't too many gamers out there who don't play shooters or will not play a shooter. In fact, I doubt there are too many people who haven't played one at any one point in their life. I'll play one for a few days or maybe even a week, depending on how interested I am or how long the game is and my will to beat it. I have had my ups and downs with most, and the downfall normally comes from restarted mechanics or roller coaster difficulty or bad story. Resistance: Fall of Man is a game that generally has all three of those but sold amazingly well for some reason. Halo 3 and 2 also have those same characteristics ( The reason I omit Halo: Combat Evolved is because I loved the game because it was hands down a great game for the period).
The game that I have most recently played is S.T.A.L.K.E.R: Shadow of Chernobyl. Many who might read this probably think I'm a moron for playing but I do so that I love the game. It glitches so often and has no motivation except the mysterious story, but I can't say I hate the idea of an open world FPS. One thing I hate about most FPS's is that they are linear and have a very sustained rate of progression and specified choke points. S.T.A.L.K.E.R. doesn't share that. You can do whatever you want and kill whoever you want, save the traders. Go anywhere and kill anyone are two things I liked about Oblivion (Which is another game I come back to a lot).
I also recently upgraded (replaced) my old (dead) video card and now I can view all of its prettyness. Screen Shots don't do the game justice because they don't show the grass and trees and wind all swaying and moving and alive. Inside environments and night time environments really shine because the lighting in the game is its best highlight. I really do like the graphics, although they are way too system heavy for a game that doesn't look nearly as good as it should for its weight. I can't say its ugly though. I am generally excited about the coming prequel as well, and I hope that the game doesn't require Nasa to play, seeing how it looks ten times better than a game that looked alright and ran like shit.
S.T.A.L.K.E.R. is also a difficult game. It combines the realism and frustration of a game like Counter Strike: Source and the lack of auto saves such as the ones in Oblivion. The first mission of the game on its easiest difficulty is easy to say more difficult than the entirety of a few games on their hardest difficulty (Rouge Trooper). Saving often is the only way to counter act this, because the only way to get a new gun without having to pay out the ass, is to kill other guys who have better guns than you. Unless you find one that is hidden or off a dead body in the middle of no where, namely a place you shouldn't be because a guy with a better gun and more bullets than you couldn't survive.
The glitches in the game are very bad as well. I lost a save once because I accidentally saved while dead. I don't know why the designer decided that you could do that, but when I loaded back up, not only was I dead, but I was sent to bad design hell. I don't even know what happened, I was underground or some shit and clipped into the ground, or hell or something, but I also had a gun in my hand that I couldn't shoot. There have also been many times where dead enemies fell through the ground, or would clip in and out of the ground. When it rains, there are artifacts everywhere, not even artifacts created by the rain, everything seems to feel like doing the same, even the sky, which turns yellow for some reason. A friend of mine couldn't play because he had a yellow sky, a bright, glowing yellow sky (with shaders on) or no sky (with shaders off). I don't know why this happened, but we thought a patch would work, but it did not and made things worse. The guy who stands out in front of the bar also glitches and repeats the same line over and over again. I love the game, but I hope this is all fixed in Clear Sky.
I love the combat though. The guns are all different and really show their advantages and disadvantages. The bad part of the weapons is that there is a constant progression of better guns or guns that you wouldn't want or buy. The pistols really shot this, because each pistol has slightly better specs than the last. They are realistic though and make gun fights both interesting and frustrating. It isn't funny when your primary runs out of ammo, or when you have another primary with you, but the guy(s) you are shooting at are completely out of range. It makes looting bodies very important, and even picking up guns and taking their clips, which is time consuming and much more difficult to do in a fire fight because you have a weight limit (or a limit that causes your endurance, which governs your ability to sprint and jump, to go down really fast with it reached).
There is also the ability to sneak around if you wish. You are given two bars:one for the amount of noise you make and the other for your personal visibility. I generally don't sneak around too often, but when I need to, or don't feel like (don't have the resources for) getting into a large fire fight, the meters are very useful.
Overall, I love the game and I think everyone who enjoys an FPS should give it a try or two.