In one word: Fantastic.
Running it on a mid-end laptop and can get a constant 30FPS at 1920x1080 with nearly everything on high (only textures on very high and Shaders on Normal), with some FXAA and Vsync.
If you're having perfomance issues, Shaders is the biggest hit. I was disappointed with the performance initially but turning the shaders down from High to Normal helped a lot and the visual hit isn't huge.
Game looks gorgeous also - 2k textures and non-compressed movies mean you can't tell the scene transitions (usually it's noticeable because everyone encodes their video at 720 and the drop really stands out, not the case here).