Well, I just finished it.
The majority of the aircraft carrier part was fine, but the final battle out on the deck totally sucked.
It seemed really thrown together and was more irritating than fun because of the flying creatures that kept coming back to shoot the hell out of me.
There also wasn't any direction or hints while fighting the big spider robot and I had no idea that I was supposed to just keep shooting the body. It seemed to do damage for a little while, then it just stopped responding when I shot. I kept trying to shoot the legs and to run around the deck. I ended up firing some grenades at the body in desperation and it fell right over.
Then the part with the big ship was pretty much the same, except when I was supposed to use the tac cannon the game bugged and wouldn't let me lock on. I sat around trying to figure out what to do (while the people on the radio repeated the same thing over and over) and eventually got killed. When I respawned, the gun worked fine and it was over in a couple minutes.
The ending scene with the ship sinking was also unimpressive compared to the rest of the game. It was a cool scene but the visuals just seemed sort of bland for some reason.
I was very disappointed with the last level, but if (when) they make an expansion I'll pick it up. Overall, I give the game an 8/10. It'd be a 9/10 if the end portion wasn't lacking in so many areas. Crytek definitely knows how to make a great game, but it seems like they should have tested the last part of the game a hell of a lot more than they did to make sure it was free of bugs and was actually enjoyable.