Well here it goes for what its worth.
Dawn of war 2
-1920x1200, Ultra settings-
8800GT:Avg FPS - 28.15
Max FPS - 57.94
Min FPS - 2.9
470 GTX: Avg FPS - 49.94
Max FPS - 104.37
Min FPS - 24.43
Definitely a noticeable improvement while playing.
Just Cause 2
-Optimal settings (maxxed out), AA 4x, AF 16x, 1920x1200-
8800GT : Dark Tower 11.81 fps
Completion time: 161 secs
Desert Sunrise - 16.74 fps
Completion time: 120 secs
Concrete Jungle - 9.54
Completion time: 150 secs
470 GTX : Dark Tower - 26.30 fps
Completion time: 120 secs
Desert Sunrise - 29.94 fps
Completion time: 118
Concrete Jungle - 20 fps
Completion time: 94 secs
Please note that the benchmark mode seems to be capped at 30 fps. Perhaps some tweaking is in order.
Gotta say, this is quite a jump up from my 8800GT.
Only downside is that its a power hog and runs pretty hot and loud. Hoping someone will release a aftermarket heatsink in the near future as summer is coming soon.