I'm not totally sold. It's all about canned templates, and me sitting there saying "How do I change this? Is it even possible?" Then I seem to spend a long time clicking around trying to do something that is pretty easy to do in InDesign.
What is interesting, though, is you preview your iBook on an iPad that you hook up to your computer. That was cool, though it also made me frustrated as I wanted to know how to change it to single page view instead of fluid scrolling. I think the answer to that might be to make it a PDF and what the hell, just do it in InDesign.
I exported a PDF so you can view it on a computer, and not have to buy an iPad and go through Apple's store just to check it out. Be kind—this isn't edited or designed, and I couldn't figure out how to do most basic things in iBooks Author. I dragged the first two chapters of MariesWorldTour.com 2001 into it, the original Marie-leave-New York posts.
Download here. Right-click to view it in Acrobat and not the web browser, where it doesn't work right.