Call of Duty: Black Ops III will have less features on older generation consoles. According to the Call of Duty blog, the PS3 and Xbox 360 versions will not come with a single player campaign.
Here’s what Activision wrote:
The ambitious scope of the 1-4 player coop Campaign design of the PS4, Xbox One and PC versions could not be faithfully recreated on old generation hardware
The past gen consoles will still have multiplayer mode with all the features including the momentum-based movement system and Specialist classes. Plus, players will still be able to access to Shadows of Evil, Black Ops III’s new Zombies mode, which features an adventure inspired by 1940s film-noir.
Activision also pointed out that Weapon Paint Shop and the eSports tools for Black Ops III will only be available on PC, PS4, and Xbox One.