While it is almost certain Sony’s PlayStation 4 will necessitate a day one patch to update firmware, Microsoft’s Xbox One approach is decidedly important. The internet connection will render games playable outside of an online environment, zapping the previously required 24-hour check system Microsoft was putting in place before pulling the plug.
Said update could also be delivered via disc-based software purchases or USB thumbstick, if the previous generation norms persist into Xbox One’s lifespan. Note that those methods have not been confirmed.
For some time, users could order discs direct from Microsoft with the new firmware on them. That program ended sometime ago, long before NXE took over Dashboards. Worst case scenario could still allow the company to issue the same type of disc for internet-less buyers.