I think the X stands for "pony"
Gates paid like $15Million for the rights to madonna's ray of light for the xp ad campaign.... or rather, MS paid that.
I am running xp at home, and I personally don't like it and will go back to win2kpro (I had server before), but that's not to say that it isn't good - I just have enough important shit on my system that I can't have it crashing that much (under win2k, I never had it crash, and occassionally could make a program crash - under zp I've never had it crash - it just reboots when it isn't happy... at least the reboot round trip is faster now)