could this be a textbook?

Apple.iPod.40G.jpg Aural learning. Podcasting your reading assignment. New powers for students to time-shift materials and work. Load up chapter five on your iPod and take it to go.
Dyslexia’s defeat?
Publishers must be noticing all the earbuds in students’ ears.. how can they make some noise in that space?
But how do you take notes, make annotations on audio? How do you evaluate learning? Could this be anything more than a supplement?