http://digital-textbooks.blogspot.com/ Gerry McKiernan offers some perspectives on eTextbooks.
Bradley Wheeler gave a great overview of the state of Electronic Textbooks and provided many links to programs at various higher educational institutions. An archive of the Educause presentation: http://net.educause.edu/Archives/2719 The presentation was originally given on January 24th.
http://www.educause.edu/blog/aciavonne/JointheConversationontheFuture/245274 Educause has started an eText constituent group. Feel free to join the listserv.