iPad UI vs book UI

In the previous blog I compared borrowing a library e-book (for iPad) and a hardcopy book. This time I'd like to compare the User Interfaces (UI) of the two.
We all know how a book works. Behind the cover there's often a foreword and a table of contents and then comes the story or whatever content. 
What an e-book is depends on the reading device, in this case an iPad, and the reading App, in my case the Bluefire. 
I'll start with the iPad and assume the e-book is already in the iPad. To start reading you must start the Bluefire app. Next you select the book, which you'll recognize from its cover, by clicking on it. If you were reading the book, say the day before, you will come to the page where you left off, otherwise you'll see either the foreword or the table of contents. Reading is quite pleasant. Compared to some paperbacks, the iPad will feel somewhat heavy. That's the downside of iPad reading. There's a long list of advantages. The contrast is very good. You can read in darkness. You can use a larger or smaller font. You can search the whole text. You can bookmark as many pages as you like. You sweep over the screen to move to the next page. You can lie down on your back or your side or just sit down reading. 
How about the book's User Interface? With some books you have to press on it so it doesn't inadvertently change pages, or hold the page firmly. A book page is rarely flat; there's usually a bulge on one side of the page, due to the book's spine. The font of the book is decided by the printer and not by you, the reader. Once set, it can't be changed. The only help you can get is a magnifying glass. The contrast depends on the ambient light. Low light, low contrast. Search? Forget it. Bookmarking? Sure you can create pig's ears or use a fancy leather bookmark or whatever. Surely dropping a book isn't such a big deal whereas dropping the iPad will break it? No. You may have trouble finding the right page in your book, but dropping the iPad is very unlikely to hurt it. Just pick it up and start reading again; no browsing is necessary.
Aren't there any advantages to a book then? Yes there are. Losing it is probably less expensive than losing your iPad. iPads are attractive devices that you can use for lots of things, so they're theft prone. You're likelier to lose an iPad than a book. The iPad's book reading characteristics depend very much on the App used for reading. I expect to see innovations in the area once e-books become more popular. If you're not convinced already, I think you will be convinced in a few years that the book has been beaten by the iPad.