The most impressive ebooks on the iPad aren’t ebooks at all, but dedicated iOS apps. With the power of HTML5, CSS3, Javascript and ePUB3, though, there’s no reason that has to be the case at all: you can put together a truly interactive, animated ebook right within iBooks.
Check out this awesome look at the iBook put together by Walrus Books for the upcoming Lovecraftian tome Kadath: The Guide To The Unknown City. Not only does it feature interactive maps, embedded fonts, integrated pop-ups and more, but it even has its own in-book meta game and version of in-app purchases.
This is super cool. I wish we saw more iBooks like this, but unfortunately, it seems like most publishers design their ebooks for the lowest common denominator platform — the Kindle.