The Zero Dark Thirty Map Pack is available at no extra cost with the Limited or Deluxe Editions. It is inspired by a decade-long manhunt in some of the world's most dangerous places: Darra Gun Market and Chitral Compound.
Darra is home to dozens of back-alley shops and self-taught machinists making guns by hand. Chitral is highly inaccessible and was thought to be one of Bin Laden's hideouts -- only those with the capabilities of total surprise will successfully penetrate the compound.
More info can be found at http://www.medalofhonor.com/zero-dark-thirty.