Well, the first thing I should tell you, is that I'm not a Linux guy. I've always been with Microsoft; I develop in asp.net/c# primarily (although I do venture into PHP often). I prefer the range of tools with Microsoft, they're better developed and have that intuitivity (if that's a word) that many open-source projects lack.
However, I do occasionally dabble in Linux. I started with a RedHat 7 dual-boot in a laptop I had back in 01, and since then I've occasionally installed Ubuntu in dual-boot partitions. However, nothing has impressed me quite as much as the latest version of Ubuntu, coupled with KDE4.
It's great stuff. First off, the interface was great. KDE4 has a lot to say for itself; it fixes the usability problem. I like to cite the 'grandpa' test; if my grandparents can use it, then it'd be ok. And, I actually think that this might be the ticket; this could be the thing that brings Linux out of the boxes of computer engineers and into the hands of the public. I instinctively was able to move about, find things, install things (how I love the Adept package manager. Windows, take tips), run things. I was able to set up a media server with my entire media library without a hitch, following a tutorial. And it worked exactly how it was supposed to be. This is big for me. I never get Linux to run right.
That said, if you're looking to start a media server of your own, check out Jinzora2. It's an easy-to-set-up program running PHP and MySQL, and it will load your music library for you, and even find all the metadata from cover art to lyrics. Check out the tutorial I followed here and the sequel here and go for it. So far, my server's been up about a week without a hitch. I can finally say 'Yay Linux' and embrace the penguin (although in a fit of irony, I set it up using Putty from my Vista machine.)