For me, today’s news regarding electronic textbook rentals is revolutionary! Throw in the fact that it is through Amazon and their assortment of supported devices (Kindle, iOS, Android, desktop), this is an incredible advancement in learning.
A recommendation for Amazon: I would buy a Kindle (not for textbooks, but regular reading) today if I could pay a low monthly fee and read/rent all the books I wanted. I see no reason to invest up to $14 a book on an item that might not be supported in 10 years. But if I could rent the books (no ownership on my part, like a library), I would be all in.