Apple could build all this into an OSX-local service that is just a push-button away from being easy to use. Plug in an external hard drive, Log in with a special pre-configured user account, assign the drive to that user, and leave your computer running - from that point on, you can access everything that user has ever submitted, with their iDevice, over the 'net, etc.

I think the desire is definitely not there to make things this easy to use - precisely because of the Cloud-Zeitgeist that we're all involved in ..