Considering how we have heard this rumor for 4 years now - first about the Xbox 360, and now about the Xbox One I don't think it is happening, yet.
I think it's a great idea, and all digital download will be the way to go - for most consumers. Especially if they can lower the price, but I think if they were going to do this, it would have been shown at E3. They would want to show it off to the stores that would buy it and create some consumer buzz.
With a die shrink, plus dropping the Blu-ray (Which is about half the Xbox One) they could make much smaller box. Maybe something for next year's E3.