Looking at the growth of Windows 8 in the market, it has been taking off rather slowly. Windows 8 is only just edging out Vista in use in the US market (http://gs.statcounter.com/#os-US-monthly-201309-201311). Some have been comparing it to Vista, an OS bridging between XP and 7, but not reaching the global impact/sales to be a hit.
Looking back since Windows 9X, every other release was a bridge to the next OS, often leaving users to wait and leap-frog into the next operating system. The versions of ME and Vista I feel to fall into this category. Maybe they were just a little too rough around the edges for wide mainstream adoption even though they offered new technologies. They did still serve a purpose and allowed Microsoft to better refine future editions (XP and 7) which have been very successful.
Microsoft is busy working to change how Windows 8 is perceived. Improvements from the initial Windows 8 offering are available now and going beyond Windows 8.1, “Update 1” is expected in fall of 2014. These are all in response to the concerns of the general PC market to the changes in the new UI and general usability on a “mouse-first” platform. On top of these changes, Microsoft is already working on another major OS change set, currently codenamed Threshold to cross all device types (phone/tablet/PC/TV).
Threshold won’t be coming until 2015, but rumors already reference further cross-platform unification started between Windows 8 devices and the Xbox One. Additionally, expect further integration and ease of accessibility of the Microsoft Office suite of productions on devices like phones. The new CEO of Microsoft could of course change these upcoming products when he or she takes the reins in 2014. Some of the candidates have indicated potentially massive changes to the structure, including selling off the Xbox branch. It will be interesting to see how potential reprioritization will affect the roadmap for Windows and Office in the coming year.