Here`s the passage from Wired:
One night about two years ago, Panos Panay couldn’t sleep. This happens a lot, waking up in the middle of the night with loud thoughts rattling around in his head. Panay popped off the pillow, reached for his new Surface Pen and his old Surface Mini, and wrote himself an email. (He loves the Mini, a small tablet his team built but never shipped. “It was like a Moleskine,” he says. “It was awesome.”)
The Surface would`ve come right after Apple`s iPad mini, a device that is more about content consumption than creation. Microsoft decided that the differentiation of the Surface line — which includes the Pro and Book — came from its practical uses, such as the full Office suite. (Apple has since moved in this direction with the iPad Pro.)
Panay also revealed an interesting detail about the Surface Book`s "clipboard" feature: No one knew the Book was anything other than a laptop until he revealed it on stage. From Wired:
Even when Panay and his team began showing the Surface Book to partners and retailers, they never, ever detached it. “No matter what demo I do,” Panay told his team, “no matter what retail meeting I’m in, no one gets to see it with the top off.” They disabled the function, and even took the key off the keyboard. No one outside of Microsoft employees and the occasional privileged family member saw that the Book’s screen could detach until about a month before launch.
Microsoft may have also accidentally revealed the Surface Phone, a long-rumoured project that would combine the Lumia and Surface ranges into one. In the lab where new Surface devices are modelled, a "machine works on a prototype of a new phone." Given that Panay is primarily focused on Surface devices, this could be another clue that a Surface Phone is in the works.
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