Spoiler Free: For the most part, an excellent game (especially the physics), but the ending leaves much to be desired.
The graphics were on par with what you would expect from a current game and the slow motion was cool for a while. The only problem is that you can use slow motion to give you a wild advantage in every fight and you lose touch with the fast-paced action you'd expect in most shooters. This makes the game much more about surprising the enemy with ambush tactics than anything else. I'd call it's style "ambush FPS."
You better be coordinated if you want to be good at this game. You'll need to use the lean, slow-mo, crouch, med-kit, grenade, and zoom buttons a lot in battle.
The backstory was great, and the tension is perfect for a horror game. Unfortunately, I got the sense at the end of the game that they were just trying to wrap things up quickly. If you like stories with engaging themes, cool twists, and well-developed characters... this isn't it. Sure, a homicidal ghost girl and psychic commander are cool, but that's pretty much all there is to them. They leave most of the story to your imagination. Even the "big twist" at the end is just kind of... meh... I left the game without that feeling of accomplishment I got from Half-Life 2 and Doom 3.
Also, I would have liked to have seen more encounters with some of the enemies. Like I said, it seemed like they were trying to simply wrap things up toward the end. The game peaks about two levels from the end and then just kind of trails off like a guy who forgot what he was going to say.
Pros: Physics, effects, gameplay, sound, AI, everything technical
Cons: Story, last few levels (definite system hog if it matters)
Last words: Get it if you're looking for what I called an "ambush FPS," but don't expect to be blown away by the story or anything too innovative. I was a little rusty on shooters, and I found medium to be challenging, but never overwhelming. You might want to play on hard if you're a serious gamer, and easy if you're new.