I don’t really know whether Apple’s heart is in all this book stuff (Steve Jobs famously said that Americans don’t read anymore), they might not care all that much at the moment. iBooks might just be a fallback solution in case Amazon tries funny stuff (or some other competitor emerges which doesn’t want to play ball with Apple).
Prestige?
"Your laptop's so small! How do you type on that keyboard?"
"Woah, dude! The screen on your iPod's enormous! That must've cost a mint!"
[1]: http://consumerist.com/2009/06/amazon-tries-to-clarify-downl...
On the other hand, I can sort of see him telling people 'it's not my fault you wedged all those Ebooks into itunes. Are books tunes? Is e = i? No? Then get with the program!'
Edit: 'bigger than any publishers'. D'oh! They're the second biggest publicly traded company by market cap, so arguably Apple is larger than the whole book publishing sector put together in pure $ terms.
I once caught a an app that was temporarily free and got it in iTunes with my account it in one of my computers, expecting it to show up as an available download when I got back to the one I sync my phone with. It doesn't appear and I had to copy the .ipa file there.
I have no experience trying to redownload paid apps that are still the same price, but first thing I did was to add .ipa files to my daily mozy backup.