GameStop gets a replica Chimeran-teeth necklace, perfect for convincing the ladies that you wrestled and defeated an alligator. You'll also get a multiplayer booster, letting you start the multiplayer mode at level 5, and all the character customization options that come with it.
Wal-Mart shoppers get five exclusive custom name titles like "Sentinel." Amazon users get an Air Fuel Grenade in the single-player mode. Best Buyers get a Nathan Hale multiplayer skin and special taunt. Finally, Canadians (and smaller US retailers) get a Black Ops troop multiplayer skin.
Sony-published titles have tended to bunch its pre-order goodies together for a collector's edition, along with whatever other art books or statuettes come with the deluxe version. SCEA and Insomniac may be planning that for Resistance, but didn't announce any kind of CE, so for now you may just have to pick your poison.