I agree that a download is worth less than a physical book. A download is worthless unless I have a device that can read it (and works - my Cybook stopped working in the middle of my holidays, that kind of got me thinking, lol), and power to feed that device. Of course it has other advantages but it is less reliable and durable, even without the limitations of DRM. With DRM of course, the value goes down even more since the chance that I can still read it a few years from now are even slimmer.
A book may be cumbersome and less practical in some ways, but at least I can count on it at any time. With reasonable care it will still be readable 10, 30 or even 100 years from now. I can lend it, give it away or even sell it if I want to.
And of course let's not forget that a download costs significantly less to produce: no paper, no plant, no inventory, no physical distribution. Funny how increases in production costs always find their way to the end user. Decreases, somehow, seem to get lost on their way to the consumer
