The free remote play snippet was interesting. I wonder how the performance will compare to xCloud proper.
Edit: I'm sure they implied it was also running via Azure. It made me think that they're already broadcasting / recording to Azure from the console and they're probably just building on that infrastructure.
No but it would not surprise me if the console did register itself into the Xcloud or Live, that way you can connect via the central server then that drops off giving you peer to peer access. This would help with firewall issues and is how many remote pc support applications work.