Re: Free you say?
> YOU WILL NOT BE CHARGED FOR UPDATES ONCE YOU GET WINDOWS 10 FOR THE SUPPORTED LIFETIME OF THE DEVICE.
This is correct (and has been true for older Windows too), but you *will* be charged (as an indirectly absorbed cost by OEMs for pre-installed versions or directly for retail versions) if you want to get Windows 10 from 29th July 2016 onwards.
> Windows 10 is already on more than 60 million devices in 3 days of its launch.
That was always going to happen - MS have pushed this free Win 10 upgrade like crazy for months now and "who doesn't like free"? I hope people know that they've only got "30 days downgrade rights", after which time I presume a Windows downgrade involves a clean re-install (or image restore if you were clever enough to make one before the upgrade...but I bet the average user doesn't though!).
> Thats what more than the total number linux devices in the world if you take out the enterprise devices?
You've got to be careful here about what "Linux" means - if you're talking about the Linux kernel, you're on losing ground here - there are *massively* more devices running the Linux kernel then there are running Windows. Most consumer devices with a half decent CPU/RAM in them run a Linux kernel, not forgetting the metric ton load of Android devices out there.
Outside of the phone/laptop/desktop arena, Windows isn't run in many consumer-facing places (ATMs are about the most common one I can think of and many banks are considering Linux to replace Windows ATMs).
Windows still dominates in the desktop arena, that's for sure, but some of this dominance can be laid at the feet of the major OEMs, who rarely want to ship machines with anything but Windows. It's less comfy in the laptop segment because of Chromebooks and convertible tablets running Android. In the phone segment, Windows is hopeless and show no signs of joining the big two any day now.
It may be that "universal" Windows 10 helps - if a lot more popular apps turn up for Windows 10 Phone because of it, it could gain some market share there. Having been in the Insider Preview programme myself, Windows 10 seems fine once you get Classic Shell on it and as long as the Modern interface stays hidden from me on the desktop, I'm quite happy with it. It'll still only get 5% computer time from me, since my CentOS desktop is much more functional and productive in my books.