What's the purpose of the eject button on the MacBook Air? I was interested to see that the power button on the new Airs has been moved to the keyboard, and was anticipating that it would just replace the eject key that has traditionally taken up that position.

However, this appears not to be the case (pic is from iFixit's teardown guide):



What's the purpose of the eject key with no optical drive?
There's also quite a few keyboard shortcuts that use the eject key. 


Control ⌃+Eject ⏏ brings up a screen that has Restart/Sleep/Cancel/Shut Down options
Command ⌘+Control ⌃+Eject ⏏ instantly restarts
(etc.)