From Joystiq:
http://www.joystiq.com/2013/05/01/call-of-duty-ghosts-announced-next-gen-powered-by-new-engine/
Call of Duty: Ghosts announced; next-gen powered by new engine
Activision will debut the next-gen version of Call of Duty: Ghosts – and revealing its new engine to the world – during Microsoft's upcoming Xbox 'Next Generation' event on May 21.
Ghosts features an "all-new gameplay experience built on an entirely new story, setting and cast of characters," the press release further detailed.
An onslaught of additional info and explosion-filled marketing is expected closer to E3 2013.
Update: The website theghostsarereal.com – designed to look like an official Activision site – lists Wii U as a platform for the next Call of Duty title. Activision tells Joystiq the website is not owned or operated by the publisher. No Wii U version has been announced.