Capcom has done a bit of clarity for those who will be obtainable bonuses from GameStop.com will come Resident Evil 6 at specific stores : these will consist of three different maps for Mercenaries mode. Details below and its screen.

The Catacombs available through pre-order at GameStop/EB Games

A map set in ancient catacombs full of traps and monsters of all kinds ready to attack us from all angles.

High Seas Fortress available time pre-order at Amazon.com
Ourselves on the deck of an aircraft carrier in a hangar. We are engaged in gunfights on the bridge but there will be more direct confrontations with bare hands with the enemies inside the hangar spaces.

Rail Yard available by preorder from Best Buy
Map set within a rail yard with enemies that can jump out and trains from the roof of the building itself. You will need to be continually moving to hope to survive.

Please note that Resident Evil 6 arrives next October 2 in stores.