I think we shouldn't have to worry about the obsolescence of our eBooks. Every device should support the reading of text (.txt) files as a minimum. Every file format should allow the extraction of the text to a text file. That way, if I spend money for a book, I know I can keep it forever and read it as many times as I wish. eReaders may change, but they will always read text files.
I know: This is somewhat of an idealistic fantasy. Text files are not perfect representations of what everyone wants in an eBook. We need 16-bit character formats for some languages. Not every eReader allows reading text files. Text is not always extractable from DRMed files. Pinocchio was a fictional character.
We should insist on a baseline functionality. All readers should support text files. All books should be either convertible to text files or obtainable as text files. We can include 16-bit character encoding in this standard. The people at Project Gutenberg understand this.
In Asia, one can pick up a cheap Mp4 player with a fairly big screen that will display text files for reading. Maybe I have to re-format the files to compensate for the fact that Asian engineers think word wrap is an extravagant frill. But it is quick and easy to do. So I can have an OK reader for about US$100. You can find them on eBay.
Anyone who wants to rent eBooks by buying them in a DRMed format should be allowed to do so without criticism. Whenever I take a driving vacation with my family, I rent a car. I like to put the high mileage on someone else's vehicle, and I like a new car for a road trip. Buying DRM is just a small extravagance -- like ice cream on a hot day.
