The only reason I have Win 8 on one of my 8 PC's in my house, is to run the Netflix App, which is the ONLY way you can get 5800bps "Super HD" to work on a PC right now. It'll work on other devices, but they aren't windows based. So, if you run a home theater PC as I do and do most of your stuff on your main TV with it like me, and you don't want to watch Netflix in 1700kpbs "Regular HD", and want the really good picture, Win 8 is the ONLY option. I researched this high and low before spending one of my 15$ Win7 upgrade tickets for Win8 before the expired.
Gaming systems are all still Win7, and will be until something better than Win8 comes along, or I'm forced to change in order to keep up with current tech/games.
I agree with Chalenge as well 100%, Windows isn't going anywhere, and OS's like Linux and what not will be a niche thing at best for years to come, unless all the software developers decided at once to abandon Microsoft, which will never happen IMO.