With the download I got from google books, I was unable to use Find. Um, that's the one primary reason to get electronic copy. I know there is a page with some useful text on it...I can search...well, not this one... Next, the book isn't formatted properly, so the table of contents doesn't show up in the side bar. If you are going to use ADE, you might as well invest in porting the book over entirely.
(edited again as the lameness continues to add up)
Lack of copy means you should actually use things like active links since I can't copy. There are references to additional documentation for jquery site and I have to type them in manually.
(edited after actually reading through some of the book)
After working through a number of chapters, I've decided this is a completely useless product. See the attached picture of how nice the fonts look. Some parts are readable at full screen, others look like a bad scanned image from 1982. Hopefully you guys have better technology available to you-but, I'm seriously starting to wonder. This is shot from a widescreen monitor oriented portrait...so, it's a nice 21'' screen tall.

If I see that O'Reilly has moved to a more modern approach to publications, maybe I'll be a customer again, but not until it's perfectly obvious that you've ditched ADE and allowed customers to actually use the books in ways that make them most useful.