Comment 5 for bug 531495

"Switch off" is poor terminology that does not accurately describe what happens when the menu option is selected.

http://www.google.com/dictionary?aq=f&langpair=en|en&q=switch+off&hl=en

"switch off
    PHRASAL VERB
    If you switch off a light or other electrical device, you stop it working by operating a switch."

Clicking "switch off" usually removes power from the computer, but is not the same as physically operating a switch that turns the computer off.

"Shut down" works. "Shut off" works. "Power down" or "Power off" may work.

"Shut down" is probably the best option, as it just as accurately describes the act of shutting down power to the computer as it does halting the operating system so that the user may "power down" the computer manually using a physical switch or button. There's probably a reason that "shut down" it the terminology that has been in use up until now.