An excellent sequel, short in single-player but multiplayer takes it to a new level.
First of all, the Single-Player Campaign, though shorter, does feel a lot more fun and better to play. With desperate hold-out situations, addictive helicopter firefights and the sheer fun of ordering your support around, you'll feel straight in the middle of a battlefield. The Crosscom now also gives you the chance to see the battle through the eyes of your support, fomr soldiers, drones to tanks and choppers, you can see what they're doing and give orders through this view. This really gives you the edge of an effective firefight without having to really stick your head out and risk being shot.
A new array of weapons gives a lot more interest in the replayability of the game, including new sub-machine guns as side arms (only deatured in the GRAW 1 PC Version) and new weapons such as an automatic Grenade Launcher, you'll find it a lot of fun to replay levels thinking 'What if I used this weapon here?'. All in all the Single Player part of GRAW 2 pumps some adrenaline into you for sure, but it is still quite short in length, thus the Achievements are more multiplayer focused.
As for multiplayer, it's been tweaked to night-on perfection. Although you still can't use cover in multiplayer, the new multiplayer content is so big than you won't care about having to stand openly to fight. A wide new range of maps, increasingly addictive Co-op missions, and a wide range of weapons make sure Multiplayer is all it's cracked up to be. Better still, you won't be killed straight away sometimes too, when you are hit, but not killed, you may go into a critical state meaning you roll about until you die or are helped by a friend. This really adds to the tension as you sprint to a teamate, or shout into your microphone that you're dying out there, expect some dramatic sequences with this.
The Co-op missions are really quite replayable, you can go through once with all-guns blazing, or go through with stealth, and coordination. The mission changes as you use each tactic, making it worth going through agian. Achievements are quite simple to earn, most of them involve killing so many of this, or completing that, with a bit or work it isn't a problem.
So, the final word is, an excellent, replayable game, though a short and relatively small SIngle-player, you'll get a massive, fun multiplayer that'll last for a good while. Not recommened for those who aren't on Live Gold of course, but it's still worth a good play if you like Tactical Shooters/Modern Warfare games.