I've been using GNU/Linux as both desktop and server OS for years now.
I'm at the point where I'm much less productive in windows, and generally get really frustrated using it. Even though once upon a time I used to use and develop in it frequently.
In my experience, setting up things the way you want it takes much longer in GNU/Linux, but the end result is ever so much worth every single minute spent.
I don't really like going into the whole Freedom debate since it is a minefield full of opinions. Some see the GPL as freedom and others see it as restrictive. It's probably both! It prevents developers from making non-Free(as in freedom) software (don't forget you can still sell software for money under the GPL.). This creates a situation where a vast array of Free development libraries is available which you can modify, edit, build upon, use, abuse, etc, as long as your program is also free. I think, as a developer, that one restriction for the developer, to make your software Free, is very much worth the restriction (of not being able to make your software non-Free.).
Over the years, "arcane" configuration files are not arcane at all, to me, GUI's feel arcane. This is all a matter of what you're used to, one is not superior over the other.
I don't think any one should push one other into any one operating system. Each OS has it's pro's and con's to different people. Right now there is more windows users on dc than there is GNU/Linux fellows, and I'd love to see DC become a place where both can share their experiences in peace without namecalling and prejudgementalisms (is that a word?
). Especially now that cross-platform applications are becoming more common and widespread, there is no reason for that not to be possible.
It has to be said though, that the more I grow into one OS the more I outgrow the other, and despite the availability of more cross platform applications, they are still vastly different worlds and require vastly different mindsets to use to their full potential.