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Are you saying there will be no more versions of Windows after Windows 10?
Microsoft is moving Windows to a servicing model with Windows 10. The days of major revisions or what are called big bang releases are no more. As Microsoft Program Manager for Windows Terry Myerson described it:
This is more than a one-time upgrade: once a Windows device is upgraded to Windows 10, we will continue to keep it current for the supported lifetime of the device – at no additional charge. With Windows 10, the experience will evolve and get even better over time. We’ll deliver new features when they’re ready, not waiting for the next major release. We think of Windows as a Service – in fact, one could reasonably think of Windows in the next couple of years as one of the largest Internet services on the planet.
And just like any Internet service, the idea of asking "What version are you on?" will cease to make sense – which is great news for our Windows developers.
Source: http://blogs.windows.com/bloggingwindows/2015/01/21/the-next-generation-of-windows-windows-10/
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