-the .app packaging format. The icon is the entire app. Just drag it to the trash to uninstall it. No registry fragments left behind.
Not quite true as the 'Library' settings are still left in either the 'System' level library or the 'Users' level library depending on the application. What I would really like to see (and I have just started dipping my hand in development on Mac OS X) is, say an applescript in the .app folder that would detect being moved to the Trash and prompt the user to clean-up the applications settings etc. Does anyone know if this is possible?