Treyarch is most likely now planning CoD, Possibly for Black Ops 2 or World at War 2. They have started hiring people for these or other projects.
Activision is sticking with Treyarch’s Call of Duty: Black Ops. With this confirmation, the Treyarch is calling for game developers and designers to help them solidify Black Ops. The announcement is posted on their website where they added multiple job listings.
Descriptions of the job vacancies has mentioned on the urgency for the Call of Duty’s Gameplay combat designer and Scripter for the single level player creation. It is also thought that Infinity Ward are working with Raven Software and Sledgehammer Games on the next Call of Duty video game which we expect it to be either Black Ops or World War 2.
With regards to release date, many believe that it would be either this late 2011 or early 2012. Treyarch job listings surely confirms these rumors.