From the Gameflavor Network preview:
"Castle Wolfenstein is back with more zombie-fighting action set in WWII Germany, but can it capture the attention of First Person Shooter fans in a genre crowded with modern titles?
Early screens for the game have been somewhat disappointing, visually. Player models appear to have low polygon counts, while some surfaces appear unnaturally bumpy and shiny. Contrary to earlier speculation, the title does not run on id's new The 5 graphics engine. Rather, the game has been developed using a modified version of the Quake 3 engine, which is already beginning to show its age."