My PRS-600 battery discharge is not due to being plugged into any USB port. Mine was not plugged into anything. The Kindle 2 was also a battery drainer. I was hoping that my 600 would be more like my 505 was, the 505 held a battery charge pretty much as advertised. Also, I do not use it to play MP3s or view photos.

I do realise that new LiON batteries sometimes have to be completely (or nearly completely) discharged and recharged a few times before they reach their full potential. So perhaps this issue will improve over time.

komugi, Your comment about the case pressing the page turn button was interesting. Did this drain your 700 battery even when it was turned off?

I wonder if the Device Shutdown option will help. I'll try that, although it takes a while to turn on when completely shutdown. But shuuting down every night would not be to much of an inconvenience.