The last M$ computer in the house just got wiped and replaced with Ubuntu linux. That makes 4, a knoppmyth BE/FE, a knoppmyth FE in the bedroom, and two desktops. This last one was the kid's computer, and it remained a winbox for some games. Lately they've just been playing net games though, so I saw it as an opportunity to clean house.
Install goes pretty smooth with Ubuntu, which is a debian variant. I was curious to try it and may keep it around for a while. Apt-get got me mythfrontend, mythvideo, etc. Nice. Still need to get mplayer working, but live tv and recordings are excellent.