on lower end PC's but i tried it with Crysis.
here's the system.
ADM Phenom 9500 (Quad 2.2GHz)
2Gb DDR2 RAM
ATI 3870HD (512Mb)
i ran windows XP (i was dual booting) and used crysis in DX9. i got
pretty sweet graphics, but still was cartoonesque. when i booted up
into Vista (unfortuneately) i ran Crysis in DX10. In DX10 i came across
far superior graphics than i did with DX9, i don't have screenshots
because it didn't appeal to me to take any (and i'm not going to
reinstall windows to get pictures) but try it out if you want. like i
said, i tried it on a low end system and didn't notice much difference.
low end being: Pentium 4 3.0GHz 1.5GB RAM, NVidia Geforce 8500GT (256MB)
and i noticed almost nothing. so i can see the argument. but when you
have a computer worth talking about, it makes a HUGE difference.