Animations and interactivity
There has been some criticisim of early submissions from iBA for their lack of interactivity/animation.
I have been having great sucess using Keynote to generate animated files for use in iBA. I have generated some very snappy Intro Media files by creating a 1024x768 slide, animating to my heart's content and then exporting as quicktime video (converting to Apple TV format so iBA accepts it). I have also played some very complex Keynote presentations via the Keynote widget.
I have the advantage of being quite proficient at Keynote (and keynote animations in particular) but if you're haing trouble getting some pazzazz into your book take a look at generating some stuff in Keynote. It's very cool!
iBook Author-OTHER, Mac OS X (10.7.2)