I t hink you guys are forgetting the *other* possible graphics card available at this time: The Radeon.
The D3D engine of UT is not bad, it's just that Nvidia based cards don't support Pallatized Textures while rendering in D3D (that's why the OpenGL renderers are available). The Radeon and the Voodoo's on the other hand *do* support this texture format in all API's, whereas Nvidia only supports it in OpenGL.
Here's the thing though, on AnandTech, SharkyExtreme, TomsHardware, etc, Nvidia based graphics cards ALWAYS score better on the UT benchmarks, which is something I've never understood. Except for a Geforce3, I haven't come across any Nvidia based card that could run UT as smoothly as a Voodoo5 or a Radeon.
I myself have a Radeon SE and INF runs amazing. I play at 1600x1200 and still get 35-55fps smoothly. I think I'm more dependant on my 1.2ghz processor actually. It only slows down when I'm looking at the entire map after I've died. =P