I currently run WinXP, Suse, Red Hat and Ubuntu. I've not met with the Linux distro that I love, but I will be giving up Windows as soon as they try and force Vista on me. I have no intention of ever upgrading, and almost regret moving off of W2K. Software authorization is a complete joke (having to ask for permission to run software that was legally purchased, what a rip off) and won't be purchasing any software that uses it from here on out.
I've never been thrilled with Mac's either, price point on the systems has not been competitive until recently. Now that they run on intel, that barrier will go away. Even though I've never owned a Mac, I have a version of OSX that will run on a Wintel box. I need to load that one too...
-RAnthony