LEGO MINDSTORMS EV3 Essentials by Abid H. Mujtaba in a new offering from PACKT Publishing. I was able to review the ebook over the last couple weeks.
PACKT did a good job in publishing the book in color. The book presents the EV3 in great details. It goes over each sensor and motor and includes comments on using NXT electronics with EV3. However, some of the images used were out of focus or looked cropped. The screen captures of the EV3 screen were good quality, which is key to understanding what is going one. That said, if you want a summary of EV3 hardware, there are better books out there. You might consider another option.
Where this book really shined (albeit a bit unusual approach, by not actually talking about some of the really cool tools of leJOS) is that it provided an overview of Java leJOS on EV3. It goes over some basic Linux settings (wifi among other things) on the brick. It goes over IDEs and Makefiles. The book provides some good sample programs to get you started. It sort of assumes you have some exposure to Java and Linux, but not much on MINDSTORMS.
Overall I would recommend this book if you want to do Java on EV3 and have some Linux exposure. However, there is some room for improvement. Naturally, it is LEGO and MINDSTORMS, not Lego nor Mindstorms. Lastly, leJOS has some impressive tools out of the box that seem to be ignored.