Activision just announced with a blog post that Call of Duty: Black Ops III will actually come to PS3 and Xbox 360 on top of the previously announced PC, PS4 and Xbox One versions.
Beenox and Mercenary Technology are the studios working on the old-gen ports.
There will be differences with the current generation version: the campaign co-op mode will only allow two players instead of four on PS3 and Xbox 360, while “some other features and functionality” will also not be included, as they’re built specifically for the new generation of platforms.
The upcoming beta will also be available only on PS4, Xbox One and PC.
As a bit of a punch in the gut for Wii U owners (at least the fifteen that actually care about Call of Duty, I guess), the announcement explicitly specifies that there is no version of the game planned for Nintendo’s console.