A picture of a pre order card was sent in to IGN, that showed the name and date of the next Call Of Duty game, 11.13.12. 

If you want full official confirmation, Activision anounced there will be a trailer May 1 during The NBA Playoff night.

Check out more at  http://www.g4tv.com/thefeed/blog/post/723277/call-of-duty-black-ops-2-release-date-and-title-leak/