Now it's called compiz-fusion and it's a set of plugins for compiz, but I'm with BooDaddy on that: GUIs on linux have made an outstanting progress in the last years.
There are way better fonts than Windows or OSX, the alsa sound driver is very powerful and the responsiveness is way, way, [put any number of "way" here] better than Windows and OSX put togheter.
Video drivers also are better, I've had more problems recently with ATI/NVidia Windows drivers than on linux.
When I use Windows, either XP or Vista, I really feel like there is something that isn't right. It's just not responsive and smooth as it's on my Xfce, and it makes me nervous.
And, by the way, aren't you mad when some full screen interface, like a game, crashes on Windows and alt+tab doesn't work? Well, on linux you have the SysRq magic key, from which you can kill whatever is running on the given terminal (like, say, X), remount disks read-only or sync them before rebooting, and it works in ANY case (even on a kernel crash). Just to mention one of the many linux differences I couldn't live without
Of course, I still have to boot on (or emulate) Windows sometimes to play a videogame or use some advanced software, but this isn't linux's fault, is it?
