yea you get the tracer dart pistol, m1a1 sub-machine gun, the m1911, improver vehicle armor,vehicle alternative fire, vehicle motion sensor. thats in the Limited Edition
and for preordering the limited edition from gamestop you get the AKS-74
and if you preorder it online from gamestop you get guaranteed(i think) access to the beta
All of the Pre-order and Limited Edition bonuses are not exclusive. You will eventually unlock them all in the standard game.