It's funny, I have an easier time getting friends/family on to a usable Linux OS than myself. I tend to use windows on the desktop (more about cost/value) and OSX for my laptops... I run Linux for my HTPC, and on servers.
I run multiple monitors and multiple drives in my desktop, and generally one of those two things will lead me to pain when it comes to installation, or an upgrade cycle with the OS. I really don't like playing with my desktop for a half a day to get it running again when I'm trying to get work done.
Given, it's a lot better today than in years past, I just haven't had it in me to go to Linux for a month, only to have an update break something that will take hours to fix. That just doesn't happen as much in OSX or Windows.
I kind of wish one desktop platform would come to true prominence in Linux, and I care less about which one, as any one... then that one can get a lot better. I don't even mind gnome 3 or unity so much. I just want something that will keep working right through a few upgrade cycles... opposed to where I really consider not running updates on my desktop.
My last attempt at Linux for a primary OS was about a year and a half ago. I tend to get the bug to try it out every couple years. Eventually, I hit a wall a week or few weeks in that I just don't have time/patience to deal with.
PC-BSD was also a really nice option, but the limited VM options and support for current hardware really killed that for me. I think BSD fits my mindset better, but Linux has become more ubiquitous.
Either way, I would love to see a truly great desktop Linux platform for me. A power user and programmer who likes to tinker with stuff, but wants something that has an ok ui, that gets regular updates without issue. Most of the time, when I did update, it was more for something I wanted to play with other than the main OS.