The XO/PS4 generation will last for quite awhile. After that, I think we'll have another generation of home consoles. After that? It's too far away to speculate.
The thing is, people keep saying that set-top boxes will replace home consoles but I see no evidence of that happening anytime soon because home consoles can do what set-top boxes can do while delivering much better games. It's like people saying that bicycles will replace motorcycles. As far as I can tell, there is a market for both.
Will set-top boxes be able to stream CoD one day? Sure, but the state of the world's internet is far from that being an option for everyone. I live in the US and there is no internet in my area fast enough to meet the Playstation Now requirements.
