I think it is a big change that students need to buy their books. Right now, schools frequently buy books and then keep them for years upon years, just renting them out to students. This change will increase textbook competition, and increase the rate of change of material.
It also means that generating different versions of text books (Texas vs. rest of the US) might make a lot more sense.
Given this answer (and the amount of downvoting on my previous statement), I think that I might have been ambiguous and left too much space for misunderstandings.
What I am challenging is not the overall value of the initiative (through market effects such as competition), but its technological side: given our parent post's first paragraph, what is Apple's contribution to the current e-textbook toolset? Digital textbooks offer much potential for improving certain kinds of cognitive tasks in both sciences and humanities — the former being exemplified by gfodor. However, from this standpoint, I do not see a significant step forward; rather, I see the promulgation of what are mostly "vanity" features that offer limited additional value for study and learning over traditional tools, and which are often styled with a certain kind of eyecandy that I personally find distracting and detrimental in productive contexts.
It also means that generating different versions of text books (Texas vs. rest of the US) might make a lot more sense.