The display of my new Kindle 4 just got broken one week before the next extensive trip.
I instantly contacted Amazon via the web interface, they automatically called me back via phone.
Basically the support agent asked me if it fell down or was in contact with water. Then he directly started the process of sending me one as a replacement.
Luckily I got the replacement one on time. Thanks for the good customer support Amazon.
2015-05-09 Short update:
2nd Kindle still works flawless, the Amazon Kindle Zip Sleeve protects it for two years now.