Incredible Adventures of Van Helsing Cheats
(Usually this is the case with all titles offering x86 and x64 executables although there might be minor performance gains on 64-bit as well.)
Should the developers choose to they could of course include additional effects to better take advantage of 64-bit capabilities though this isn't very common, Call of Duty: Ghosts is using the additional memory for various things (Though it's 64-bit only.) and Battlefield 4 has cloth physics and some enhanced effects when you start the 64-bit exe.
But again I don't think there's anything special for this game.