Well, we're talking next gen, right? Xbox One is already here, so it's not like they will just can it and proceed right away. They can definitely have a Kinect with its own processor(s) by then, or they could also just offload the processing to whatever future devices it'll connect to.
As for streaming, yeah, they'll need to get crackin' on it or just buy someone with technology in place already, like OnLive. That, or they can just do what they are currently doing with Xbox LIVE on Windows Phone and just have Xbox LIVE-branded mobile games and just track Achievements and whatnot.