With Call of Duty Black Ops II being revealed a few hours ago, Gamestop isn't wasting any time with offering pre-order incentives. If you pre-order the game now you'll gain access to Modern Warfare 3 perks. In addition, if you pre-order before June 30th you can get an instantly redeemable MW 3 prestige token, the catch you have to be a PowerUp rewards member. Oh I forgot to mention that you also get a poster.
GameStop has plans to announced additional pre-order bonuses and depending on when you pre-order you can get all of them or just some of the bonuses.