I'm going to predict that the time is right for some investor to start a new PC company, and the only OS offered will be Linux. It will be very low cost and he will sweep in and completely change the dynamic. He'll do it by going to every grammar school, high school and University in the country and offering essentially at-cost computers to the staff, and killer deals for the students. One generation of this and you can kiss Microsoft's dominance goodbye. It's not like it's a big secret that Microsoft is, and has been, terrified of this kind of scenario, and it's in part what drives their hyper-aggressive marketing and business tactics.
Investors usually have money and the way they keep their money is to not make mistakes. There is a problem with Linux; it's open source! Pouring money into it would be a mistake!
The problem is that Linux wants to push that open source mentality down to the application layer and NOBODY writes commercial software for Linux. They MIGHT port a Windows application, after it is up and selling, but they won't develop one from scratch. The 'open source' is half of the problem and the users wanting something for nothing is the other half. If companies can't make money writing software, they won't write it!
On the desktop, Linux is going nowhere. After 20+ years it still accounts for less than 2% of desktops and it won't be improving any time soon.
Linux, at the command line, brings a Unix time-share flavor and I rather like doing software development from the command line. I still use gedit for the editor but I am perfectly comfortable using Makefiles.
Yes, Unity is a piece of crap. The sheer arrogance of putting the system buttons on the wrong side is inexcusable! I haven't tried Mint but I have heard good things about it. Next time I set up a Linux box I'll give it a shot. And, yes, I realize that I can search the Internet and find the solution to the buttons problem. But I shouldn't have to!
Actually, people have been writing commercial software for Linux for a LONG time, and it's growing, not shrinking. The only thing really missing that most people might use everyday is Microsoft Office. Of course, there is a lot of specialty software that simply doesn't exist in Linux. Some CAD suites, PCB suites, Adobe's software, and things like that.
But consider that a huge amount of internet infrastructure is built on Linux and Android is also built on Linux.
The only thing Linux is really missing is a decent desktop. Cinnamon is more than decent. There's really very little reason to ever go a shell if you don't want to, though there are still some rough edges and it kind of annoys me that instead of polishing them, they keep concentrating on adding crap. For example, I needed to edit my rc.local file to change my touchpad hysteresis settings in order to make it usable. That's COMPLETELY inexcusable, and if anything it's brain damaged thinking like this, and brain damaged thinking going on at places like Canonical, that is keeping people away.
Which is why the smart investor will NOT use some random distribution for his hardware. They will take the Apple approach and will assemble a distribution which is tailored to their hardware, and it will truly just work and work well. Not just well but far better than Windows, and at least as well as OSX.
Millions of people use Linux everyday and have no clue it's Linux. The only problem with getting Linux on desktops is guys like GNU, which by and large encourages an unfocused, random, dumpster-like approach to software, and guys like Canonical who I can only guess are being bribed by Microsoft and Apple. Not only can Linux take over the desktop market (and I do believe that it can, and will, in my lifetime), but with the right front end it can be so good that it can actually be used to sell the hardware, just as OSX and Android sell the hardware.
Anyway, follow the games. IMHO, it's always been gaming that has held back both Apple and Linux. I see signs already that gaming can, and will, come to Linux in a significant way, and that'll be that.