Wired already has gotten its hands on the Xbox One ahead of time, and as a result, has a bit of in-depth information to report beyond what's been seen in Microsoft's presentation. For starters, the outlet learned that the Xbox One is not backwards compatible, stating "Neither of their new machines are backward compatible with their current ones. That means your seven years’ worth of digital game purchases made over the Xbox Live Marketplace won’t function on the new machine."
Allegedly licenses for movies, music and other content will be transferred over, but not games -- at least, as far as Wired knows. Well...that could be a major problem, especially considering Microsoft was a beacon of hope for digital rights, linking Xbox Live accounts years before Sony and Nintendo even thought of it (and for that matter, Nintendo still hasn't truly implemented it).
If you were watching the presentation you'd see that Microsoft is focusing more on entertainment than Sony, something Wired also picked up on during its hands-on time. On the game side of things however, it seems as if you can install any game to the console itself, and play without the disc -- and the installation seems mandatory, and according to Wired, may be tied to an Xbox Live account. After a second account gets ahold of the disc, the new owner will have the option to pay a fee and install the game -- effectively fighting piracy/rampant disc sharing. Wired explains the issue a bit more, saying, "since [copying] is clearly not going to happen, each disc must then only install for a single owner."
Whether this goes so far as to "shut down" the disc entirely, Microsoft wouldn't answer. One thing's for sure, I'm not keen on the backwards compatibility news, but it seems as if "always on" has effectively been debunked in some capacity.
How Xbox One [Wired]