So it's not always online, but the disc is tied to a Live account in order to play? I don't see this going over very well.

Also, if people can pay an additional fee for a used game to be tied to their system, then what's to stop people from renting or borrowing the game, downloading it, then paying $10 dollars to have ownership of the game permanently? Unless once the Xbox logs back online ownership is switched, and if the other owner wants to regain ownership they'll need to purchase the code once more.