I'd bet it would change by the time they announced these final details. To be not 10 shares but say 3 shares with specific devices with peeps you've been friends with for like 6 mos or something.
There's no way they could of came out post E3 and say "oh that sharing plan, yeah its limited to one hour per game."
That's a damn demo that PS4 is including automatically even if no one you know owns the game.