I checked out all the major Ereaders and found they are totally connected to particular providers, from whom you must buy the books. Personally, I still prefer holding a book in my hands. But I do recognize the future of publishing is electronic. I think there will be a universal E receiver pretty soon.
I am concerned that when there is NO paper trail, something can cease to exist, including important documents, historical thought, and so forth. Some day there might be very little evidence of this civilization. All we have for some past peoples are marks on stone walls and cemeteries. We might not even have that!