One of the things about the PC version of
Mirror's Edge is the fact that it will take advantage of NVIDIA's PhysX technology to give you some really cool effects. Below you can see the comparison video and how much different it looks with the feature on than off. The changes are pretty drastic so it's not something that you're not going to see when you run it using PhysX. I have to say it looks pretty impressive and I might have to drop my NVIDIA card in to play the game when it gets released on the PC.