2) I suspect (and this is a bit of a pet theory of mine) that Apple stays in the ebook
space primarily to disrupt the
educational textbook market (I think that iBooks Author + iTunesU + «cheap» iPad 2s = a strategy for fostering disruption in education at the grass - roots level); their presence in trade publishing is relatively incidental (this may have not been so at the start — I also suspect that launching iBooks
along with iPad was initially a hedge against uncertainty about user adoption and viable use cases for the iPad.