I just saw on G4 (the videogame channel) that those stills are nothing more than concept images. Neither the Xbox nor the PS2 are capable of creating gameplay graphics that sharp, which is why they are considered concept images for what the Xbox 2 version will probably look like.

"Growing up my dad was like 'You have a great last name, Galifianakis. Galifianakis...begins with a gal...and ends with a kiss...' I'm like that's great dad, can we get it changed to 'Galifianafuck' please?" -- Zach Galifianakis