"Who wants a stylus? You have to get 'em, put 'em away, you lose 'em. Yuck! Nobody wants a stylus. So let's not use a stylus." -Steve Jobs
For navigating and general use on a 3.5" screen, he was dead on. For drawing on a screen of any size, especially a 12" one, the stylus makes plenty of sense.
Marketing just pushed styli (?) and hardware keyboards out, the latter is something I really miss on my phone...