I have been having this problem since beta, but i didn't reported because i thought the problem was with my old drivers. Well, after the beta closed i've updated my drivers to the most recent but the problem continues.
When my ship is in motion the shadows and some of the window decals flicker a lot, and its damn ugly.
I get the same problem. It's usually worse when loading to a new area. Also, it doesn't always do it, just sometimes. Various details and effects on the screen will flash to black. It's very distracting. The only other game I have a problem with is Dungeon Keeper 2, and that is ancient in game terms.
I am running an Geforce 8800 GTS in Win 7. And yes, I have the latest drivers and whatnot.
I hit this issue today when I took my Constitution out for a spin. The shadows were grainy and flickered across the hull randomly.
I had also noticed much earlier (Closed Beta, even) that there was some weird artifacting on the wall textures, but couldn't quite figure out what was wrong. Now I'm pretty sure the artifacting was this shadows issue.
Anyhow, I set shadows to LOW and didn't notice any significant degradation of image quality in space. We'll see what happens on the ground. Earthdock looked fine, at least.
For reference: ATI Radeon HD 4890
All features maxed except for Dynamic Lighting, which is turned off to workaround ground combat crash bug and now Shadows set to LOW.