The Chronicle of Higher Education has a very useful article about student reaction to e- texts at Northwest Missouri State that indicates widepsread use of e- texts are a number of years in the future , see http://chronicle.com/infotech, “6 Lessons Campus Learned About E-textbooks”
NW Missouri has been a leader in e text use but students found the texts awkward to navigate inside the e-text format. 40% of students said they studied less becasue of the e-texts. It was hard to highlight or enlarge the text,or share notes with other students. The biggest student problem was battery life. Marketing students found the dense tables in the e-text hard to use.
Despite these and other problems President Dean Hubbard thinks the flaws will be overcome and e-texts will be common on college campuses. He thinks it will spread like convenience stores in gas stations after the first few adopters are satisfied. I wonder about k12 adoption though because of the need to retrain so many teachers to use e-texts.