I wanted to add one more thing... It seems that the primary reason for most people to run Linux is because "it isn't Windows"...
I think you're confusing cause and effect, people ask why you don't use Windows and the answer is because you want to use something other than Windows. Particularly when the person you're talking to doesn't feel the same things chafing, maybe even though it works for you it doesn't work for me and it's not just about "being different" but that we have different needs or priorities. Just like every graphics tool discussion usually ends up with why you don't use Photoshop. It's the way of things when one tool has ~90% market share.
This doesn't strike me as enough of a reason for it to go anywhere. You and I post on Slashdot, so we don't count. The average person uses Windows, has for most of their computer life, and sees no reason to change.
The "average person" also used Internet Explorer when it had 95% market share and was really slow at seeking alternatives. Because IE6 worked because sites had to work in IE6, the mainstream only follows once a significant portion of early adopters have led the way. Not that Linux has too many trendsetters, we're "experts" but soccer moms don't take car advice from race car drivers. They want to know what works for a soccer mom.
Market share is a battle won one step at the time. Either you double 1% to 2% and get a few more to care or you halve to 0.5% and a few less care. That the 90%+ didn't care and still don't care is something that might change if you get the pebble rolling into a landslide, but if the pebble's stuck you're stuck. It's not about making Linux a killer gaming platform, it's about making gaming not be a Linux-killer. If that makes it viable for another 1%, you're making progress.
So I guess the question is... other than "It isn't Windows", what reason does John and Jane Q. Public have to even think about Linux?
Still not much, I must admit I thought Linux would be different after playing with it for 15+ years. On the other hand, it hasn't faded away into obscurity. It does get significantly easier and better to use, but so does the competition. And times change, it almost had it once when we had wired desktops plugged in the wall. Then mobile came and sleep modes and power management matters. Wired went Wireless and Bluetooth and so on. And now recently touch is the new hype. I think when it's more like a car, where a car from ten years ago is very much the same that Linux will catch up. It's morphing too much.