I've just finished this game, so I figured I'd give a spoiler-free rundown on it. The third game is essentially the perfection of what GSC Game World failed to do in the first two games. The first game (Shadow of Chernobyl) had superb atmosphere and entertainment, but it had loads of technical problems and a very difficult to use interface. The second game (Clear Sky) vastly improved the technical aspect and introduced a lot of features that had been missing in the first game, but it ruined the great solo-explorer feel of the game with poorly implemented faction warfare.
Call of Pripyat takes all of the great improvements of Clear Sky and layers them on top of the fun solo-explorer/survivor aspect of the first game. The result is very enjoyable. The basic storyline is that you are a military agent sent into the zone to find out what happened to a military expedition that disappeared. You're given a few a basic goals and the main storyline goes from there, but there's a lot of other side missions to go on for individuals and factions. The survival aspect is also present. You start out with a basic suit and gun, but you need to get far better equipment to survive and push into the more dangerous areas. Like in the first game, money can be hard to come by in Call of Pripyat. Traders will buy guns, but only if they are in good condition and that's not how you usually find them. Repairing weapons and armor costs a lot of money so even when you can make a profit by first repairing a gun and then selling it, the profit is relatively minimal. Money comes primarily from doing quests and from selling artifacts. Artifact hunting uses the much-improved Clear Sky system, with detectors of various qualities that are required to find them.
The weapon and armor system is the best of any of the games. There are repair/upgrade people in the major camps and if you find the proper tools for them, you can open up a very large selection of upgrades. This is a great system because every single weapon and armor in the entire game (with one exception) can be upgraded in all kinds of interesting and useful ways. The maps themselves are also changed, in that there are fewer (only 3) but they are much larger. From what I've read, each map is about 3 times the size of any of the maps in the other games, and that seems about right. There are certainly plenty of areas to explore and lots of interesting loot to find.
The storyline is not as interesting as the first game, but it's acceptable enough. IMO, the main draw of all the STALKER games is the survival-sandbox aspect, not the plotline. As with all the other games, the English translations and the voice acting are abysmal. Also as with the other games, Call of Pripyat has a high difficulty level. People who have played the other games will probably be used to it, maybe even finding it maybe a little easier than the others. However, it would probably be frustratingly difficult at first for people new to the series. Technically, Call of Pripyat is very stable. The entire time I played it, it crashed only twice, which isn't bad. In addition, the only noticeable bugs I saw involved some odd spawning and AI activity at the major safe areas, none of which ever really caused any problems.
Overall, I give it two thumbs up. It's currently available for $30 on Steam, or $20 if you already own either of the first two games via Steam. Both of those prices are decent value for money IMHO.
