You might have to wait to play it until later this year, but its definitely worth pre-ordering a copy of Crysis 2.
CD Wow are currently charging £24.29 to ensure that your copy of the game for PC arrives on it's release date, and will make you a saving of just over £2.50 on the next best offer of £26.91 from Amazon.
In the list of sequels to get excited about this year, Crysis 2 would definitely be among the top contenders. The original is by far the best looking game that I've ever played, standing head and shoulders above the crowd when it was released and still holding its own several years later. The nanosuit effectively turned you into a gun wielding super hero, with abilities that allowed you to either stealthily creep through a heavily guarded enemy outpost, or annihilate every soldier you came across.
Finally, the destructibility of the environments was truly jaw dropping, for example bits of sheet metal and scaffolding poles would break apart and realistically scatter around the environment after you'd thrown a grenade into a lookout tower. However, one of the especially nice touches about this was that the pieces of shrapnel and debris flying around actually posed a significant risk to your character; on one occasion I was watching a friend of mine tear through a group of enemies, the next thing we knew he'd dropped dead to the floor. Confused, we watched a replay of his final moments, and discovered to our amazement that an oil barrel he'd shot earlier had exploded, causing it to fly across the battlefield with enough force to kill him when it finally collided with his back!
There are a couple of features, which I'm particularly looking forward to in the new game. This time around you'll get to fight in New York City, instead of scrabbling around the jungle, which means you'll have many more ways to plan your attacks, and you'll be able to enter buildings and run around their numerous floors. The nanosuit has also been upgraded, making its predecessor look obsolete, and there will be times when you can combine its powers to initiate devastating attacks!
Even if Crysis 2 only slightly improves on the original, in my opinion it'll still be a fantastic game and definitely worth the pre-order price.