User blog comment:Damac1214/Unconfirmed and Unlikely: Call of Duty 9 set in the Future?/@comment-1263839-20120418161544

Guys, it is not completely unrealistic. If you look at it in the World at War 3 perspective.

World at War 42-5 (unknown for Zombies)

Black Ops 62-69 (presumabley 2000's if you count CotD aswell)

So taking another leap isn't unrealistic.