Sledgehammer Games held an AMA on Reddit regarding many new features ahead for Modern Warfare III and addressing concerns that some fans may have. One of the game modes that we know is returning will be Gunfight which is a 2v2 mode where you are timed to kill the enemy team in under a minute.
There will be 6 2v2 maps in rotation in Season 1 for Gunfight including four Carry-Forward maps from Modern Warfare II and a brand new map, Training Facility. Sledgehammer Games also confirmed that Shipment will make a return once again.
Thanks to CharlieIntel for pointing this out.