Jaunty brought with it a handy shutdown/restart delay that helps to stop erroneous shutdowns or accidental restarts by simply introducing a countdown.
It’s a handy feature but if it is bugging you, here’s the simple solution on how to remove it: -
1. Right-click the User Switcher applet (the button you use to logout)
2. Go to Preferences
3. Uncheck “Show confirmation window”
4. Hit ‘Close’.