Ow, and skinnable even!
I just installed it on my home-server (Ubuntu 8.10). Although I can't get the pretty splash-screen to work, I love it!
Especially with the remote-control abilities and a touchscreen, it's one of the nicest pieces of software I've seen recently.
Only thing I'm missing is the ability to overlay fullscreen video to my Secondary Monitor (TV) on my Home Server. (Not possible yet

http://xbmc.org
I like it, anyone got any experience with it? If not, give it a shot, it's very, very extensively supported!