episode 83 of my podcast I did a comparison of the Amazon Kindle, the Barnes & Noble Nook and the Sony eReader. And one of the big points that made the Kindle the hands down winner for me was the battery life. The advertised battery life was given as 30 days with the network turned off, which is double the life of the Nook is advertised as doing about two weeks.
So as an experiment, I decided in April to test this. I charged my Kindle overnight on 30 April, then packed away the USB cable and chose not to use it again until the battery was drained. All updates to it were sent via wireless (I don't have the 3G, so all downloads were over wifi) and I did send several PDFs to the device.
I also reset my Kindle at one point to clean things up when I realized I had a bunch of PDFs that I no longer needed on the device. I then redownloaded all of my Kindle books to the device.
As of today, 13 June 2011, I finally got the error message that the battery was too low and needed to be charged. That's 44 days on the one charge.
Again, I feel absolutely happy in choosing the Kindle, and love my wife for having given it to me for Christmas this past year.