Uhh... looking at this little animation flipping between the Radeon 9800 and the Det 50's...
To me it looks like....
The Det 50's are better for close up stuff (not counting the darkness, but detail)...and the 9800 is better for distant stuff.
With the Det 50's... there seems to be thicker grass, more detail in the actual ground texture, and you can see the lug nuts on the wheels.
What bugs me is the stuff in the distance.
The 9800 is much sharper for the explosion and fragments... and the ship in the distance is better "lit", clearer... and things in general that are distant are more clear / sharp.
that said... I think they both suck in their own ways... and both rock in their own ways.
I'm still prolly going ATi for my next card tho.