The really promising indicator for Pop Sci isn’t the one-week sales leap of 13 percent — it’s that the the magazine’s growth picked up after that week, with more velocity.
What I really remember about Steve Jobs presenting the iPad was that he talked about content and getting people to pay for it. Apple understands that the internet and technology brings about new possibilities but if you work with content providers you can creatively transition their business models to new technology so that industries don't get destroyed.
Publishers love standard interfaces to deliver their rich content and the iPad gives them that. Amazon also understands that which is why I don't believe they will stray too far from their initial 7" screen of the Kindle Fire.
Apple understands that the physical constraints of touch interfaces require accompanying standardized hardware constraints. It's another reason why gaming is hugely popular on iOS. Gaming on Android isn't as popular as it is extremely difficult to deliver the same gaming experience on multiple sizes of touch screens.