I'd argue that relative to "Consumer Awareness", Linux is actually 2nd to Microsoft in usage.
Everyone has heard of Windows and most desktop PCs run it (> 90%).
Almost no one has heard of Linux (only IT workers and computer enthusiasts) and yet it is run on 1% - 2% of desktop PCs.
What's Apple's excuse?
Everyone has heard of Apple and yet it can only manage ~7% of the desktop PC market.
The problem with Apple is they aren't tech heads. Jobs was. Jobs collected technologies like it was a hobby. Its not just about where you've been, and where you are, but where you can be based on whats currently out there. Both Apple, Microsoft, and Google are at the end of a chain of development. They didn't create LED's. They didn't create run-time operating systems. They certainly didn't create the technologies say the Internet was based on. They take whats available, typically buy it out, and evolve it into usable products to enhance their core lines. Its not about what you would Like to do... its about what Can be done.
Right now both Apple and Google are feeding into the media's perception that its all about The Next Great Device. For Google, the Glasses thing actually seems pretty solid. They looked at a problem(people always looking down and monitoring their phones), and put a lot of current tech together to try to come up with an acceptable solution. Whether it will sell or not? Thats for the market to decide. Part of that is they have the core people in Larry Page and Sergey Brin that have a feel for what technologies are feasible to make.
Apple(and their braindead fanbase), have exactly two statements that tell me they don't have a clue other than they want The New.
The first is 'touch on desktops and laptops is pointless'. They've allready been proven wrong on the latter, they WILL be proven wrong on the former. ANYTHING that doesn't have the ability to go touch(even if you don't use it very much) is going to be a dead technology soon enough.
The second is 'Desktops are going to be obsolete, they're going away.'. Uh, try no.. with an extra helping of NO. Desktop PC's aren't going anywhere. There will always be a setup that can torch a mobile device, simply because of the form factor. You think your stuff is hot now? Wait until Intel starts finding a way to commercially sell their teraflop boards to home users. All it takes is a killer app.
And no, no gamer(not talking about those for whom Angry Birds is the highlight of their day) worth his salt can game with a crap mobile card. If it aint 60fps, the lag will destroy you. Video cards are lightyears beyond what you find in any mobile device. If Intel locks down the computation side, and drops a teraflop on your desktop, you're going to see games being developed that will be impossible on any console for a good while.
Whether they have the foresight or not to do that is another story. I'd like to think that the main reason they formatted to a PCI-e form factor is precisely to jump the technology in the home, while still selling enmasse for data centers and supercomputers. Going massively parallel(50+ cores off a card) in the home is really the only place for the desktop to go for true game-changing performance.
And also bear in mind that if you even sold 20K boards for home use, those home users could then build the world's largest ad hoc supercomputer. Imagine if you sold hundreds of thousands or millions.