I just came across a new ebook creation tool on Mashable. A group of Italian developers have just released Baker Ebook Framework, which is supposed to reduce the amount of work needed to make an ebook for the iPad.
I have a couple problems with it, though. There's the basic issue of designing an ebook for only one platform (a no-no), and then there's the fact it doesn't have a landscape mode. Sometimes people will want to use both orientations.
Sample ebook (in iTunes)