http://www.slate.com/articles/technology/bitwise/2015/08/windows_10_privacy_problems_here_s_how_bad_they_are_and_how_to_plug_them.html

Windows 10 is the operating system Microsoft needs. In other words, it’s not Windows 8, a Frankenstein’s monster of a tablet-plus-desktop OS that alienated everyone from PC manufacturers to corporate users. Instead, Windows 10 is an incremental improvement on Windows 7, one that is faster, slicker, and has some new bells and whistles, like virtual desktops and functional tablet support. One of Windows 10’s leaps, unfortunately, is straight into your personal data.