I found it strange that the Kindle has a sleep mode but it doesn't really sleep. It will continue to use the wireless connection to download updates and subscriptions in this mode. It also displays different pictures while it sleeps.  The Kindle 2 will go into sleep mode manually by sliding and releasing the power switch or automatically after 10 minutes of inactivity.

Interesting enough, the Kindle will go into sleep mode even if the mp3 music player is on with no interruption to listening. Unfortunately, you will need to wake it to stop the music. It doesn't seem to have any affect on battery life (unless the wireless is turned off). So essentially sleep mode is really just a screen saver. You would think there would be an option to set the time it automatically sleeps or turn it off entirely. So what do you think...is it a benefit or nuisance?