Several news outlets are reporting that Infinity Ward and Sledgehammer games might have already started working on possible “Classic” or “Remastered” versions of previous Modern Warfare maps for MW3 as it appears there might be some files hidden on the game disc. Keep in mind these are only map names found and are subject to change. Also there is no indication the maps were already finished prior to launch.
According to WeTheGamerz, “..there are some extra map files along side group of standard multiplayer maps that share names with maps from previous members of the Modern Warfare family.”
Maps from CoD4: Modern Warfare:
Maps from Modern Warfare 2:
Once again, this is all unconfirmed, however once we hear anything we’ll let you know.