Xbox One details: connecting online, licensing, Kinect privacy

[pvaapuri]

- Up to ten members of your family can log in and play from your shared games library on any Xbox One

Does this mean if I buy one game, then me and nine of my friends can all play that one game at the same time? or is it that they can access the game but the system first verifies that nobody else is playing it and then lets you play it (so technically only one person can play it at a time)?