eTextbook iBooks on the iPad?

I see some real potential for textbooks and students. It’s hard to tell at this point, but it looks like the actual iBook app on the just-announced iPad is not particularly geared toward research-type reading – annotation, notes, integrated multimedia – but then again, maybe it is. Either way, a well-made eTextbook app could take care of that. A big question I have is the whole ‘eye-strain’ issue that e-paper solves. Will the illuminated screen of the iPad prohibit long-session reading? If not, is e-paper and e-ink dead? So soon?