I have it running at High on 1680x1050 with 0AA, with some DX10 hacks, and get around 18-20fps. Not great, but with motion blur on, it seems a bit more.
The games graphics dissapoint me now though. I was playing it at 1024x768 on my friends PC on a CRT monitor with all the hacks on, and WHAT A DIFFERENCE
Even the extra shadowing made all the difference.
I may set the game up on my HD TV downstairs when I can be bothered so I can run it at native with all on.