It would be great if Apple would execute a bit of an update and normalize that USB port. As you should know, USB goodies are abundant and offer all kinds of potential upside. For example, along with your idea, a normal USB port could bring back local storage options for those that would like to sync their content, rather than streaming everthing- just hook up whatever size USB storage you desire.
Assuming an App store is coming, a normal USB port could let a company like Elgato pair some of their USB harware with an app to add DVR functionality, local TV tuners for free over-the-air network HD programming, etc. Some people wish it had a BD option; a normalized USB and a third party hardware player could add that as an option. Etc.
All that said, the old

TV also came with a USB port deemed "for service only"- just like the new one. It was launched in 2006, and we've had a version of "face time" called "iChat" since that time. 4 years later- unless you go with hacks to extend USB functionality- it is still officially for service only.
Based solely on that track record, I wouldn't get my hopes up too high. It's easy to imagine the applications if Apple would do it, but after 4 years of imagining the same applications, I'm a bit cynical that we'll get a different result this time.