The demo is pretty short. Here are my impressions
-Graphics are amazing, really makes you feel like you are in a war zone with everything that is going on.
-The AI (on normal) is not bad, but not great either. They always look for cover before shooting at you, but there was a couple of times where they could have shot at me while running for cover, instead they didnt and died w/o putting up a fight.
-The weight of the game is pretty ridiculous compared to other FPS, I felt VERY slow. It wasn't that the sensitivity was too low (like most games have that "weight" feel) because I changed it and it didn't "feel" right when I was moving around. That's gonna take some getting used to.
-Based on the feel, and the weight and how you move, I can tell that this game will not be for every one (unless they take their time to play it and get used to it, instead of judging it right off the bat). Hell, this game is so realistic that when u jump, u can still feel the weight instead of that floaty like jump that most (all?) FPS games have.
-Your buddies helping you out are pretty good, I did have to practically take care of the helghast myself, but I didn't feel like I "HAD" to. In fact, they took out a few that I didn't see coming.
-Alternate 2 is the best control setup imo :P
Bonus: at the end of the demo, they showed the ballet of death trailer, with words of reviews it has gotten, and it seemed great. Honestly, they have the best possible commercial they could have at the end of this demo, Sony PLEASE dont fuck this up.
Im going in for round 2 :)