Windows as a whole is doing well but that is mostly Windows 7 and XP. Windows 8 is not doing well at all. Windows 8 is just the new Vista at this point. Odds are that Windows 8 will never surpass the marketshare held by Windows 7. You could even make a reasonable comparison of Windows 8 to Windows ME.
Thing is Vista and ME failed because of bugs and other technical problems, Windows 8 was a gamble that backfired due to its interface.So these are different reasons for failure. While Windows 8 might be a mostly technically sound operating system to say the least it is one of the most controversial. As TV Tropes would put things, Windows 8 has created a broken base, divided between the people that like the changes or are indifferent to them and the ones like me, who hate the Metro UI and the start screen. My hatred of Windows 8 is very strong. I despise it as I see the Metro UI and start screen as a threat to the way computing should be.
As for the XBox One, this is another public relations disaster for Microsoft. Regardless of whatever great third party support MS might get for the X1 many gamers, myself included are going to be turned away by the fact the X1 basically has DRM, blocks used games and not to mention the Kinect camera spy device which is just paranoia fuel. I would not have a problem with the Kinect features if they were not required to be plugged in. If it was optional this would not be an issue. I am somewhat paranoid and that is why I hate this feature being required. All of the things are listed are potential deal breakers, but combined, kills any interest I have in owning an XBox One. Not to mention there is the required installs, no upgradeable HD and the fact the X1 only has 500GB on its hard drive. That might work for casual gamers but not for hardcore gamers.