XP
Quad processor
System memory 2 GB
Nvidia 250 GTS 1 GB
Direct X 9.0c updated by Game and by 1.3 patch.
In game set to High.
I have a similar issue as well, and more-so indoors than out. And mainly I see it in my Hero that I am controlling. Its just the slightest stutter every now and then. I've tried the following to get rid of it, but with no results.
1) Nvidia control panel - lowering/raising pre-rendered frames, Turning on/off Vsync, Turning on/off PhsyX.
2) In Game - Lowering/raising resolution and graphic settings.
3) Updated PhsyX, Updated Drivers
4) Nothing running in the background (By system default - Thats the way I have it rigged)
Nothing That I have done so far has had any effect. Since the issue for me is almost always indoors, I just got use to it - after playing the game for awhile.