When I was looking in my crystall ball last year I was sure that win9 and win10 will use Modern UI in a little bit improved form, that would make desktop usage a little bit easier than it was in win8... It seems that I was wrong, at leat some point of it...
My new prediction is that win9 will hide the desktop mode completely and it will be available as an compability mode for win7 (like there now is compability mode for winXP and older osses). Win10 will be the first "real" Modern UI os that don't have desktop mode at all... It has some kind of strange logic in that kind of prediction. Win 8 is a in between hybrid between "old" desktop and apps based "Modern UI" (and not completely good in neither form, though not completely bad neither). And as soon as possible the MS will move to pure Modern UI environment. It would be kind of strange if Win8 would be remembered as the last OS that supported "the Good Ole desktop environment"... and win7 as the last pure Win desktop os.
But this is only crystall ball prediction and nothing like this can not happen... or can it?
Why this could happen?
The desctop idea was to simulate normal desktop, where you have papers, machine writer, pens and other tools. But like real life desktops, the virtual desktop was allso due to the mess. A lot of stuff mixed and very good posibility that something got missed in that space (because people are lazy and not everybody keeps his desktop clean and tidy). It was tryed to remedy by using startup windows, toolbars, meta folders etc. So the idea of desktop where you can find all that you need has been faded a way. Modern UI can be as an evolutionary step further away from desktop metafora. Does it happen, remains to be seeing, but it is one possible explanation why MS seems to be abandon the desktop enviroment with win8. They think that desktop is not needed anymore. Ofcource the mobile environment has caused huge shift to that direction in anyway.