I played this for a few minutes last night just to test the performance on my machine before I really dig into the game.
Playing @ 1440p
Stock i7-3770 Non-K
Stock R9 290
8GB Ram
Settings:
Motion Blur OFF
DOF OFF - DOF is a huge performance hog
Mirror Quality Low - Didn't really test this one too much but reflections seem to be an area where modern GPU's struggle, and it's hardly necessary so I turned it down.
AA: FXAA, looks and performs better than SMAA at 1440p in my opinion.
Everything else On and set to High
Framerate:
36 - 60 FPS during gameplay, most scenes seem to average about 48-51FPS
22-60 during cutscenes
Very playable and no crashes yet so I'm not too upset with the performance, the game does seem to have a lot going on, plus decent lighting and reflections even if it doesn't look the best all over.
When I switched to 1080p I was consistently in the 50-60FPS range.
Realistically while this might not be the best port job in the world, I think PC gamers should start expecting current-gen game ports which take full advantage of console hardware (8-threaded games using 4GB+ of VRAM) to be a bit more demanding on our PC's if you want to run them 60FPS at PC resolutions. They weren't kidding around when they announced the recommended specs.