I really liked your game, there are issues yes, but overall I had really fun with it and I think it's worth the asking price as a game. I sincerely can't understand why this game is been attacked so much by fellow PC gamers and generally I believe all this negativity is a bit biased.
The single player campaign is big, one of the biggest actually I've experience in recent FPS titles I played. Furthermore it's a fun game to play. It's certainly more on rails compared to the old Crysis / Far Cry games but still there is enough freedom on how you approach your encounters and I very much like that. Some encounters favor stealth while others brute force but in any case you can most certainly play the game the way you want, which gives it a bit of better replayability value since you can try alternative strategies on future playthroughs.
Since we are talking about the "fun factor" I have to mention one of the flaws the game has, which is the AI. As have many people appointed countless times it bugs a lot. Enemies doing senseless spins, NPCs chasing butterflies while you are passing right through them etc. Personally I would like the AI to be a bit more "aggressive" at least in the higher level of difficulties because in most situations you can "turtle" defend your position easily. As a comparison I think Halo had great AI.
One flaw leads to another so my second real concern of this game is the story and everything around that. Production values are top notch with nice voiceovers, settings, direction, videos and all but the characters and the way the story evolves is a bit meh... I wouldn't call the story bad but in no way it "svcks you in", caring about what will happen (let's say like... yeah easy guess Half Life 2). I would just call it mediocre.
Too much negativity and this post supposed to be a thumbs up so let's get back to the pros. I loved the NY setting and graphics, I really love them. Milk and cookies for your for making the game run so good on my humble 4870. Yes some textures are low res but seriously I don't give a flying duck. I am too busy playing the game to notice them and I don't feel like going on low res texture hunting just for the sake of it. Buildings collapse around you, bridges fall, everything is top notch and gives you the impression of a big collapsing urban city. I love how "busy" everything is. There is not a single scene that something isn't happening in the background. The game is packed with detail. Seriously in max settings and with the game in motion (not lifeless screen shots) I would take Crysis 2 any day compared to the previous Crytek games.
Plus I like the new approach in this. PC developers should aim at offering a great experience for the 150-300$ video cards not only for the +$500 ones, which really in my opinion as products shouldn't really exist. Developing PC games for medium rigs would open the market more and sales would increase. I am not saying that the games shouldn't offer something for the people that toss out a huge amount of money to get the best hardware but that games shouldn't be "balanced" around that.
Crysis 2 is a great example that others should follow, looking great in high settings and offering more eye candy in the very high and extreme settings for the better rigs. It's a nice change from games that are absolutely looking terrible in low / medium settings, which is the case usually in the PC releases. You know the games you put away to play in the next PC upgrade. Any PC game from now on, should at least offer the graphic experience of Crysis 2 in the medium range hardware. Crysis 2 is the new benchmark for me regarding my wallet anything below that in the quality / performance ratio will get axed.
Furthermore in my humble opinion, it's time us PC users start spending less money on hardware and more money on software / games. I've seen people tossing $2000+ on a PC easily but getting the "Skroutz Mc Duck" syndrome when are about to spend 30$ for a game. There is this thing PC gamers have that you know spending so much for hardware means you are morally "allowed" to pirate games since you gave a huge amount of money to the "market" to get your computer in the first place. In my eyes this mentality is wrong and we should swift some of the hardware budget to the games budget.
I am enjoying the multiplayer part too but since I am just your average player and not so much into competitive multiplayer games the certain issues the multiplayer has (like... well... cheating) aren't annoying me that much. I guess though that people who are more serious about their game would be very annoyed in the various ways the nanosuit can be abused by cheaters.
Then again I really know no FPS game that is not plagued by aimbots, wall hacks and cheats of all shorts. I mean dear developers just look at the leaderboards and especially the top 10 you will find some really odd statistics for some players. You know the not humanly possible type.
Ending this wall of text I would say that overall I liked the game, the pros are more than the cons and I really believe all this hatred is not justified so thumbs up to you Crytek. Waiting for more single content for it in the form of DLC, which is destined to come but please make it rather good. A nice example is Lair of the Shadowbroker for Mass Effect 2 a DLC that justifies its price and it's top notch quality.
To sum it up I would call the game Very Good. Enemy AI and mediocre story keep it from reaching Masterpiece status.