Bzzzzzt! Wrong answer, thanks for playing anyway.
From the rootkit fiasco on Sony music CDs I consider all media suspect and do not allow any autoplay. The "trouble" of hitting play on a CD I want to listen to (as opposed to just ripping) isn't worth the risk of it trying to install something.
Sometimes I want to put in a software disk and look at the documentation on it or try to find a driver. I don't want it starting the setup program to start installing something.
Absolutely right. I routinely nuke all autoplay and autorun keys in the registry after winstalling windows. That breaks a few odds and ends, but saves me lots of grief in the long run.