Windows Phone; Windows 7, 8, 9; Windows RT; Windows CE; and not to mention all the different variations of Windows boxed OSes (Pro, Basic, Home, and so on): there have been a lot of different products that bear the name Windows, and someone has probably decided it's time to simplify.
The idea would be that, in the mind of the consumer, Windows is just Windows, and that all of these different names and flavors are just confusing ("Why is it called Windows Phone if it can't run my Windows programs?"). Getting rid of all that complexity and returning to the old way - where Windows is synonymous with personal computing - would certainly be a coup for Microsoft. But just as it shot itself in the foot with Windows RT, consolidating on just "Windows" could be fiscal suicide if Microsoft's various operating systems don't indeed come together as one harmonious platform.
The folks at ExtremeTech have noticed a shift in nomenclature and marketing focus these days, as several products have simply discussed
Windows, with no emphasis on anything other than that single word. The challenge here is that what marketing wants can't be delivered by the technical teams behind all those different versions of Windows operating systems, as they are not just different codebases, but extremely different code bases.