Good gameplay, good co-op.
The gameplay is a new feature to get used to, especially if your are too used to FPS like Halo. It's third person, and to aim you have to press the LT button and use your right analog stick to move the crosshairs. The game also have a nice cover feature, and a very effective one too if you are neck-deep in Locust shooting at you.
The controls are nice to handle, reload takes getting used to. If you ran out of ammo, you have to press the RB button and time it right too. The other good feature is being able to sprint from A to B, making you less of a cannon fodder.
The graphics aren't really that good to look at. The colours? Dull grey with some hint to red if you are crazy enough to chainsaw your enemies up close and personal. Let's face it, it's greyer than my old secondary school uniform. But it gives the chilly atmospheric tension if you a re playing on your own.
The whole levels are hard, and that was just casual. It's not an easy game to play on your own and that's their intention. So start cracking out the bottles of cider with your mate. When you play co-op, you get to control these beefy, armour-powered marines, and start getting yourself killed with just about anything from Berserkers to not getting to the appointed spot before the timer runs out. A great way to fall out with your friends.
All in all, it's good, better if you play with your friends.