Shouldn't VRAM be dynamically scalable? But even if that's the case, i'm not sure why other games don't have this problem with textures but Ghostbusters does. Don't really accept the explanation.
Sorry , you may be right and i don't really know what's the actual technical mumbo jumbo names. But yeah the gist of what i read was PS3 had 8 whatchamacallits and 360s had less than that, so they scaled down the game, and that's why PS3 version of Ghostbusters sucks.