According to PushSquare, the base download for Call of Duty: Modern Warfare 2 is 151.4 GB, with co-op and multiplayer packs that can add a handful of bonus gigs. Even those that own the game on disc will need to wait for this massive download before they can play.
The new Ashika Island map will be the main focus of the Season 2 update, offering up new POIs for players to battle in. We can expect the new map to be roughly one-third larger than the previous small maps. The size of the Warzone 2 Season 2 update will be the same as the MW2 Season 2 update (22.1GB).