I would think that Amazon would lead the charge for an open standard for distributing video which handles DRM, subscription, pay per view, etc. and then all the non-Netflixes would publish to that standard, and let player applications thrive. Even when using a Roku it feels like each app is completely different. And most of them suck. Imagine if in 1985 Prism, HBO, and Showtime all manufactured their own TVs and required you to use them, but they all had wildly different layouts and remotes.
The idea of syncing up two video streams is awesome, I can see people enjoying that, and it would encourage people to pay for whatever services their friends have. Though it does sound a bit similar to rabb.it