I have a Nvidia card, and I'm running with the 285.38 beta drivers. I solved all my problems by doing the following.

I created a file called rageConfig.cfg in my \Steam\steamapps\common\rage\base folder. In this file, I have the following settings:

seta image_anisotropy "16"
seta image_usecompression "0"
seta image_filter "GL_LINEAR_MIPMAP_LINEAR"
seta image_lodbias "-1"
seta r_fullscreen "1"
seta r_swapInterval "1"
seta r_displayRefresh "0"
seta r_renderer "best"
seta r_multiSamples "8"
seta r_shadows "1"
seta vt_lodBias "-1"
seta vt_pageimagesizeuniquediffuseonly2 "8192"
seta vt_pageimagesizeuniquediffuseonly "8192"
seta vt_pageimagesizeunique "8192"
seta vt_pageimagesizevmtr "8192"
vt_restart


In the Nvidia Control Panel, I have Tripple buffering set to "On" and Multi-GPU rendering mode set to "Single-GPU". The rest is on default. Do this on rage.exe.

The last five lines I thing are Nvidia only. The game looks much, much better now.

From this Video:
http://www.youtube.com/watch?v=L8iaYsyN_jQ

Before:
http://www.youtube.com/watch?v=U2YgnHiDzd0

After
http://www.youtube.com/watch?v=L8iaYsyN_jQ

bump