What arguments do you have against a 'pull' style for notifications? Something like a GET to /latest that passes in the last time the client checked for updates and only gets back the URI of the last 10 or so posts since then. An HD video post could contain simply a URI that points to the video, so the video isn't even downloaded until the 'app' within tent asks for it.

This way you could have a path with all the videos on it that you could proxy off to a server with more bandwidth. It would get the user a lot more control over how their content is accessed.

Edit: And what if my server is down when one of my friends makes a post? Will I never see it?