The other reviews are far too generous. I feel the need to warn gamers of what was not mentioned in those other reviews. There are many factors of Far Cry 2 that need to be dealt with for me to show any interest in a Far Cry 3 purchase down the road.
Most of the additional features that "attempt" to add realism are merely frustrating and tedious. You begin with the Malaria Effect. Essentially at any given moment, you can suddenly seize up with out any warning, and become crippled, often this will occur in the middle of a battle, getting you killed. This is tantamount to adding a feature to your game that makes your console crash at random intervals so that you have to restart from your last save. Fun. It also means that if you run more than 50 feet without taking a break, your vision (see Graphics) will become blurry.
The moron AI needs to understand the difference between when you are in a vehicle or not as they will try and run you down (a clever strategy if you are on foot as this results in an instant kill) even when you are in a vehicle. This amounts to every vehicle in the area driving up right in front of you and stopping, so that you can easily dispatch the vehicular threats in the area and focus on the ground troops.
Speaking of vehicles, there is the driving. Endless driving, broken up only by the constant tedious checkpoints, that regenerate troops to defend them as soon as you have driven out of line of sight. I fail to understand why they could not implement a fast travel system like Fallout 3, allowing you to instantly go anywere you have previously been to... this is supposed to be a FPS. Not a driving game.
Added to this is the inability to save whenever you want to. It's not too bad, as there are a decent number of locations that you can save, but whenever you die and have to redo a mission, this does mean you have to drive there all over again, re-clearing any checkpoints you most certainly had to pass through before, adding to the tedium this game offers. Simply preventing you from saving when enemies are present would have sufficed. I cannot express this enough, but making players do something tedious over and over and over is not fun and I am unclear as to what purpose this serves. I don't mind fighting a tough battle several times, but I don't need to spend an unnecessary 10 minutes driving to the battle for every attempt...
Then there is the gun jams. These occur in the lower end guns so bad that a submachinegun would be more efficient to throw at the enemy than to bother to attempt firing. I don't need that kind of realism. The "S" in FPS stands for shooter... thus I expect to have weapons that can shoot.
I could probably forgive most of this, except for one factor. They knew about this in Far Cry but never got around to fixing it I guess for the sequel. COVER is supposed to work BOTH ways! Even wearing full camouflage and targetting the enemy from a distance with sniper weapons, the moment you let loose one round, every enemy in the region will know exactly where you are, until the enemies have been cleared. You however will not be able to know where you are being shot at from, unless you see the bullets hitting something, giving you a vague idea of direction, or when you are shot (this gives you a red indictator for the direction of fire). Your keen awareness only seems to work when the bullets are hitting you...
I would only recommend Far Cry 2 to gamers with a great deal of free time. If you are not a patient person, BEWARE!