I bought the kindle version as Peachpit cancelled my pre-order for back order issues (still can't figure how could a digital file be on back order; neither Jeff nor the publisher gave me any explanation).
The book itself is quite nice, even if, having bought "Camera to Print and Screen" and both Lightroom 3/4 courses from LuLa, the book is more or less a recap.
Some phrases are even the same you hear on the videos. So I'd say definitely buy it if you have never watched one of the courses mentioned above.
Jeff, however, explores the birth of Lightroom with a lot of behind the scenes, which is nice for us who "live" around this software.
Being a "prosumer" (trying not to sound a know-all), I'd rate it 3/5 stars.
The Amazon Kindle version (read on the retina iPad app) is on average quality, as most of the other photography ebooks (I own a lot of them).
Mid quality layout (not ePub's fault) and very low res pictures, which is a shame because they look totally pixelated on retina display. Very few of them are mid-hi res. Maybe five or so.
Maybe a direct download from Peachpit would have been provided a better quality product, because they have separate formats for a number of devices.