A recent listing on Amazon.com has revealed that Activision will release a collection containing Call of Duty 2, Call of Duty 3 and Call of Duty: World at War on the first of June this year. The collection will be known as Call of Duty: The War Collection and is currently only listed as available for the Xbox 360.
Call of Duty 2, released in 2005, was developed by Infinity Ward. The remaining two games, Call of Duty 3 and Call of Duty: World at War were developed by Treyarch games and were released in 2006 and 2008 respectively. The original Call of Duty from 2003 was already released on Xbox Live Arcade and the Playstation Store in December 2009.