It looks like Call of Duty 2020 will be part of the Black Ops universe, and the setting is Vietnam, according to today's rumors.
Call of Duty 2020 could be called Call of Duty: Vietnam if rumors are correct.
Yesterday, TheGamingRevolution reported this year's entry in the series would not be a Black Ops title in name, as previous rumors suggested, but that it would set in the same universe during the Cold War era and with the Vietnam War taking center stage (thanks, Charlie Intel).
Fast forward to today, and Kotaku's Jason Schreier backed up the rumor in a series of tweets (thanks, resetera). He said as far as he was aware, the game would be part of the Black Ops universe, and that it would focus on the war in Vietnam - and that he doesn't think it's reboot of the original Black Ops released in 2010 which was also set during the Cold War.
Last year, a report stated Call of Duty 2020’s development had been troubled, causing Activision to bring Treyarch in on the project. It was previously rumored to be a new Black Ops title, but that was about all we knew about it.
The company tends to announce its CoD titles in May, which is just around the corner, so going by the announcement history, we can hopefully expect to hear about the new game next month.