Modern Warfare III has been released for over a week now and Sledgehammer Games revealed the three new core 6v6 maps coming to the game in Season 1. The official date when the first season of Modern Warfare III and Warzone drops has not been announced yet, but they gave a slight tease.
The three new maps coming to Call of Duty: Modern Warfare III that will become available during Season 1 are Meat, Greece, and Rio with two of them coming on Day One and the other at a later time.
Season 1 for Call of Duty: Modern Warfare III and Warzone will bring fresh modes including the fan favorite Gunfight. The developer confirmed there will be more news coming in the official Season 1 Announcement blog.
Source: Call of Duty