Please define “Distribution”

As some of you may know, I am the founder of the Utah Open Source Foundation.  On November 10, we’ll be holding the Multi-Distro Release Party, and I planned on sharing Fedora (of course), OpenSUSE and Ubuntu.  Its the only Multi-Distro Release Party going on that I know of, but I could be wrong.  If you live in Utah, you should come, it’ll be a blast!

The point of this post is to ask a simple question, however.  During the promotion of this event, I’ve received suggestions beyond the three big versions of Linux that are being released close to one month from each other.  For example, OpenBSD will be release soon, and Apple released Leopard for Mac OSX, among others.  And while every operating system is welcome to participate in the MDRP, I can’t help but wonder about certain definitions.

My question is what counts as a distro?.  I mean how do you classify yourself as a distro?  Is it a Linux only thing?  Or, is it just Open Source OSes?  Maybe its nothing, and I’m just bringing this up for no good reason.

Your comments are appreciated and encouraged.