It appears to me that MS going with the all-digital-download model for Xbox One games. Even if you buy the physical disc, the Xbox One treats it like a digital download - just copying the game from the disc rather than downloading over the network. No, MS hasn't said this explicitly but I think it's the best explanation for what they have said (in public statements and in leaked private statements).
Of course, everyone wants to know how this model will effect certain properties typical to the physical model, i.e. the ability to borrow, lend, rent, sell, trade & buy used. Traditional digital download models, i.e. iTunes & Steam, simply discard these properties. eBooks can be borrowed from libraries, but that is a intentional extra feature and not something which is inherent & implicit to eBooks. The question is whether MS will provide similar features for Xbox One games, and how those features will be implemented.
On the subject of used games, I often see the statement that game buyers consider the resale value as part of the price of a game. (i.e. a game may be $60 on the shelf, but it's really only $40 because it is worth $20 in GameStop credit.) While this may be true for people who buy games frequently, it's not true for me. I have less time than money, so I tend to buy infrequently. I also don't tend to sell my games after I have finished them.