I picked up Martin Evening's Lightroom Transformation yesterday. I have had Kelby's Lightroom Books since version 1, but as of late been disappointed by the information provided. Scott seemed to be more interested in entertaining you and showing off. I rarely read these books front to back, instead jumping to the areas that interest me.
Martin is giving great explanations for each of the functions, in Lightroom and when to jump to Photoshop. I like using clarity, but didn't understand that it was adjusting the midtones while not affecting the shadows and highlights. Martin gave examples on how and when to use it. He has the best explanations I have seen in sharpening and noise reduction. I'm only halfway through and really enjoying it.
Evening is a British author and this was obviously edited for the US market as the spelling of color and centerI are in US English. I highly recommend this book, for beginners and for those of us who have been at it and still have some questions.