There's been tons of rumors being regurgitated on The Verge, TechnoBuffalo and other tech sites over the past few months; I've seen a few pieces talking about a potential return of the start menu, the replacement of the modern UI, somehow even more unity between desktop and mobile, etc. However, one of the most interesting articles I saw was this one. It's not the exact same article I saw originally, but I just did a quick search and found one with the same source.
What I find interesting about it are some of the remarks that this guy who worked on design for Windows 8, Jacob Miller, says. Among them:
...or some other way of me trying to convince you that Metro is actually useful. I've talked about those in the past extensively on reddit, but for this discussion let's throw that all out the window. For this discussion, assume that Metro is sh*t for power users (even if you don't believe it to be).
Whatever feature we wanted to add into Windows, it had to be something that was simple enough for casual users to not get confused with, but also not dumbed down enough to be useless to power users. Many, MANY features got cut because of this.
He mentions the same cycle that Killerdude referenced, although more on a level about new features vs. improvements, as opposed to just sh*t vs. good:
Windows 7 couldn't have existed without the lessons we learned from the mess that was vista. Xp couldn't have existed without 2000. Hopefully Windows 9 will be a solid refinement on all this.
He mentions things like multiple desktops being features that have been cut in the casual vs. power user struggle. If all of this is legitimate, hopefully we'll see Windows 9 being a power user-focused operating system that brings new features to the desktop, reinstates desktop features that were removed in Windows 8, and so forth.