Worthplaying should know by know that framebuffer captures on Xbox usually are way to dark because the developers use the TV encoder chip to change the color balance. The game is dark, but certainly not as dark as that.
Some textures took a big hit (characters especially), but otherwise the game looks and plays better than on my GF4 4200 (where I have to use at least 1024x768 mode or AA on my 19" screen, of course in 640x480 it certainly plays as well). It supports widescreen btw, and the sound is simply amazing.