I love Linux, I really do. I'm writing this comment inside a virtual image of a Linux desktop since my employer won't let me install it directly to the hard drive (something about compatibility with the Microsoft tools I need to use for my job, silly people). But to say that Linux has won takes a very narrow view of the IT world and how it works.
It is fair to say that Linux has won the server side of IT. Most web servers run some variation of Linux to host the pages you view. The cloud is dominated by Linux. The majority of routers are running some version of LInux. But Linux has still not taken over the desktop, and it doesn't show any signs that it ever will. I think this is a shame because I think the Linux desktop works better than anything Microsoft has or will ever put out. Microsoft is always playing catch-up to what's new and shiny in the Linux world. But it hasn't happened in spite of confident predictions that this will be the year of the Linux desktop for the past ten to fifteen years.
For now IT is trending toward cloud services, but this has its downsides as well as advantages. It means you're sharing ownership of your intellectual property with whomever you're using to host your services, and you don't have absolute control over the security of your data the way you would if you kept it on an offline storage device. In twenty years the next big thing in IT may be quantum computing where storage is so cheap and convenient it's not necessary to do everything on the cloud. Hacking might outstrip all attempts to keep systems secure, again necessitating offline data and computation. It's impossible to predict.
I'm glad that Linux has been so successful, even if its success is hard to see from the end user perspective. But declarations of victory bother me when the field so complex.
Linux won't take over anything desktop-wise as long as graphic drivers continue sucking hard, but manufacturers have no incentive to do so as long as the crowd is too small - kind of a Catch-22 situation over there. Trying to install Catalyst with my HD6870 always have been so much fun, and the open-source drivers don't cut it overall.