Once you walk out of a building the landscape moves up and down and all around with so many curved surfaces it would make John Carmack crap his pants. When you walk out into the open you can see the ring curl up to the point that when you look straight up you can see a fine line of it on the other side. The water in this game is also some of the best I have ever seen. It ripples and bobs up and down, but its too hard to explain, you have to see it to understand. As for the animations, well they are incomparable.
Nothing comes close.
Instead Inverse Kinematics are used. This allows for the body to react life like to anything in comes in path with. For example when driving a jeep in the game, each wheel acts independently to the ground and the people inside will bob up and down accordingly. That brings me to another point the physics model. Now this may not belong in the graphics section but I'm not sure if it belongs in the game play section either.