Yes, it’s free. That’s one way Microsoft is planning to regain the operating system market. Lots of improvements: new experience, Cortana now on tablet and PCs, new web experience, new universal apps, includes Xbox Apps, new Continuum Mode, broader device support, New HoloLens holographic support, and Surface Hub with integrated Skype and OneNote. Free upgrade is available from one year of release date. See the full article here.