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See Features/ConsoleKitInhibitAPI for our plans wrt. to improved user experience for shutdown with multiple users. Our approach does not address system-wide notifications in general, but does offer more control for shutdown. E.g. a backup program that is running in the background would cause the user to get an informative dialog when he tries to shut down the system: 'System backup in progress, turning the computer off now would be bad'. --mclasen 15:54, 13 December 2009 (UTC)