I don't get why Gamespot took this so seriously. This game is a VERY good multiplayer game, and at a great price.
Gun-play: Gritty and fun. The screen shake is done right. Not annoying and adds a sense of hecticness.(I make up words, deal with it)
Variety: Great, there are great classes to be upgraded from rank 1 to 6, each rank up feeling satisfying, seeing how you get so much more powerful, and have perks. Perks such as lower prices for guns(that are meant for your class), better armor(certain classes).
Other variety is in the mutants/zeds/zombies you fight, each one mixing up how you should approach killing them.
Difficulty: Perfect. There are (I believe 5) difficulty settings, ranging from very very easy, to very very hard. There is a perfect setting for everyone.
Cons:
-Berserker(melee focused) class is unsatisfying(personal opinion, many do like it). The melee contact sounds are so quiet and are the least violent and satisfying.(again, opinion
-Stiff controls. You cannot interrupt reloading your gun. If you are being closely chased and you accidentally hit reload, you cannot stop it, you can hit the key to change to your next gun, which will only switch automatically when you are done reloading.
Overall: Great Co-op experience. NOT MEANT TO BE TAKEN SERIOUSLY, LIKE GAMESPOT DID. The voice acting is meant to be cheesy and funny. (only the gun merchant is annoying, and a dirty whore, but can be turned off in the options.) This game beats Left 4 Dead 1/2 in the PVE department, but KF has no vs. so L4D definitely is still great for just that.