Great Sequel!
The game plays identical to the original Crysis except Warhead gives you a few new weapons and equipment. It's relatively short but it's so packed with action and the long cutscenes really immerse you right back into the story.
The hardware side of the game runs a little better than the original Crysis and looks about the same save for a few small things. I just installed Windows Vista two weeks ago with all updates and drivers. Everything is supposed to run smooth right? Well, I have an 8800 GTX and apparently Nvidia and Microsoft have yet to fix their driver issue which affects this card the most. And although I fixed the drivers for other games Warhead brought a few more to the surface but with a little research and updating I was able to get the game running.
The game also comes with a multiplayer disc called Crysis Wars. I've yet to install and run it but I'm sure it'll bring even more fun to the show as Crysis' original online play was just as immersive.
If for some crazy reason you've got the rig and you haven't played the original Crysis, please play them in order. Crysis and Warhead are two epic games that shouldn't be missed.