Why is Windows 8 Innovative on Desktop?

A common trend I see among people that enjoy Windows 8 is that they'll describe the experience or the operating system as "innovative" regardless of its use-case. I'm not discrediting the notion that Windows 8 does a lot of things to change the way people work on their computer and especially their tablets; however, innovation isn't about change, it's about improvement. So I want to know how Windows 8 really innovates upon operating systems including Windows 7 and its competitors, not in general, but in a single specific use case: the desktop. A lot of people see Windows 8 (both RT and otherwise) as Microsoft's stab at the tablet market. This makes sense considering the effort that Microsoft put into making the device touch-friendly; however, unlike the other tablet operating systems, Microsoft has left the full backbone in place for intel-based tablets. This significant difference makes a Windows tablet incredibly powerful because of the programs it is capable of running; however, Microsoft still competes with conventional desktop operating systems - namely Mac OS. This leads to a divide, where desktop users might have little use for an interface that arguably makes more consideration for touch than mice. Still, many people claim Windows 8 to be innovative in full, seemingly including the desktop in the mix. My question, why?

Why is Windows 8 innovative on the Desktop?