I have been using Debian since 1996, and became a package maintainer in 1997, a position I held for nearly a decade until I began to not have enough time for it. While continuing to think that Debian is a first-rate effort, I got tired of certain aspects of it, and moved to Ubuntu, lock stock and barrel. I actually like to have my desktop system marching in sync with my server, so that the packages are pretty much exactly the same. And you know what? Ubuntu works pretty well on the server, and comes out with nice regular releases, allowing me to decide, and gauge, time-wise, when to upgrade. Certainly, like everything else, it has its defects, but by and large, I've had good luck with it, as both a desktop and server distribution.
