Originally Posted by igorsk
The Kindle's "off" switch does not actually turn the device off but just blanks the screen(same as Sony Reader). If you want to really power off the device, use the reset hole.
It is correct that the off switch does not disconnect the battery (it's not like a light switch). An engineer can determine this by measuring the battery current in various states. With WAN also off, they will likely find that screen-saver and "off" use the same current (very, very little).
It is not correct that the pin-hole reset turns Kindle off off. It restarts the device, which uses a lot of power. Igor is pretty smart, so this must be a typo on his part.
The only way to really turn it off is to yank the battery.