Professional video editing, Hollywood style.... only on linux. Professional video editing, small and medium enterprises style... go for OSX. Consumer pseudo-professional video editing.... Windows.
In broadcast, the workflow for video editing has been on linux for quite a while in the professional market, because those guys need the fastest workflow conceivable, and they can only get the edge they need (e.g. news shows, etc...) on linux. The same goes for high end video productions, i.e. Hollywood. They have been using linux solutions, although not open source, for quite a while, because there is nothing else that even comes close to the same level of power, added value (image quality) and above all, workflow, it's by far the most user friendly solution for real power users.
Same goes for audio and music productions by the way. Large broadcast consoles and huge high end productions: linux, then a very large layer of professional audio/music productions on OSX, and at the bottom, the consumer class low value productions on Windows. In audio production, there is however the linux alternative in the open source realm, in a more straightforward way than for video production.
Games: those will always be platform dependent, Nintendo is platform dependent, in fact, Nintendo has announced it's first non-Nintendo-platform license a couple of days ago for Android, and the stock value for Nintendo skyrocketed.
Entertainment is a business like that. It's the same with Amazon or Google or Apple iTunes or Netflix or whatever entertainment formula, it's about locking down, not opening up. That's why content creators for the entertainment sector are such easy victims when it comes to the closed source commercial software world, they tend to think that an open source solution is not possible, just like twenty years ago, musicians didn't think that you could have a successful music career without getting picked up by a big record company...
Nothing in the entertainment industry is honest, it's all a front for a business that you wouldn't expect at first glance. It sits in so many things: in codecs (Samsung has now broken the sacred codec alliance by making the NX1 use h.265, now it won't be long before the whole video production closed source software crappile starts to crumble lol, just like it did before with the music industry once the codecs and hardware locks became open, which happened earlier than in video because audio production industry is just a lot older), in distribution platforms (like why does YouTube not work with IPv6?), etc...
The future of Microsoft is not Windows. In fact, as we speak, Microsoft is pushing to get MS-Office delivered free preloaded (one year free, then 365 subscription) on Android phones... in particular on Sumsung, TrekStor and Lenovo tablets and phones, the deals have been made for the German market. Windows has been a great distribution platform for Microsoft, to sell their golden products on. Windows allowed them to capture the market that Apple had for spreadsheets, the market that WordPerfect had for word processing, and the market that Lotus had for groupware applications. MS-Office is what Microsoft is about. They've opened up an API (proprietary of course) to let developers make plugins for MS-Office on different platforms now. They've just fired all of their Windows devs, open sourced .NET tools, made visual studio free, and are relaying all of the Windows development to MS-Office development. Windows is not all that important any more. Even XBox prevails over Windows in the eyes of Microsoft as entertainment distribution platform. That's why Windows X will come with XBox integration. Hence "games for Windows" is a notion that just ceases to exist, it will be "games for PC", which will mean linux games, because we'll have to rip them from SteamOS basically to play on a linux PC, or "games on locked down console ecosystems", meaning Windows/Xbox, Nintendo, Playstation, Android, iOS, SteamOS, etc...
