Good luck with those installs, Belfiore
Belfiore's prediction of surpassing a billion Win10 installs is beyond ambitious and borders into the realms of sci fi. As evidenced by the dearth of demand for even a FREE Win10 upgrade on some existing Win7/8/8.1 platforms, personally, I don't see the expected demand ever happening, but then it's not up to me to burst Belfiore's ivory tower bubble.
That being said, I have yet to see a compelling reason to buy a Windows based smartphone primarily because the OS is so very bloated/buggy/insecure - and yet these drawbacks are touted as features. Seems to me, Windows smartphones are for consumers who close their eyes to the inherent insecurities of the OS because they are either unwilling or unable to learn anything about their phones beyond the absolute basics.