I agree the need to make these things more durable.
I had a PRS500 that I had dropped from about waist height in its case. Dropped it in the parking lot as I was fumbling for my keys. Anyway, about a fourth of the screen was screwed up, with permanent dark lines running across.
They can make cell phones that can be dropped and dropped again repeatedly from such a height and they keep working fine. The same needs to be done for these readers before they will really take off. It is especially sickening when you realize that to fix and replace the screen nearly matches the cost of the reader itself.