Man, I loaded this bad boy up last and WOW does it look amazing!!! I am having one problem: I can't get the screen res to go to 1600 x 1050. The game is truly gorgeous. By far the best animations I've seen, and the textures rival Half-Life 2. I'd even go so far as to say they're a little better, but it's been awhile since I've seen Half-Life 2.
The gameplay is fun. It feels a lot more like the first game than the second, which is good for me... I really didn't like Pandora Tomorrow. I don't know why, I just didn't.
I really like the loadout options they give you; it really let's you play the game the way you want to rather than cramming one method down your throat. The AI also seems to be much better. They're persistant little fsckers now, whereas in PT you could just cop a squat for a minute or so and wait for them to forget they got shot in the leg. It's more suspenseful now, too, with them carrying flares. It's cool. If they light up and come looking for you, they WILL find you unless you take evasive action (or wax them).
I'm only through the first level (and a little bit of the cruise ship, which is absolutely GORGEOUS), but so far I like it a lot.