With the uninstall, there really ought to be an option to remove
everything or to leave playlists, serial numbers etc intact. Last time we talked about this, I stated my opinion that an uninstaller should remove every single trace of its program, but of course most of them don't. I don't remember that we came to a clear decision on this.
I believe there was a consensus - and nothing happened.
The uninstaller that "installs" with 3.0 (10d) removes almost nothing. If you run the uninstaller, and then download the 11i .scr file and click on it, it works fine, including all settings, etc. And if you happen to have the 10d .scr file around, and click on that, it also works fine - no need to enter your registration code.