i thought this book was GREAT... until i had a needy (read:normal) breastfed baby. now, i find it slightly ridiculous.
it's kind of like a watered down version of Babywise. Tracy has a nice chapter on respecting your baby as an individual, yet she still has you give your baby a label- angel, textbook, grumpy, etc... like Babywise it has the scheduling thing going on in the same order- Eat, Activity, Sleep. but, Baby Whisperer is a bit more gentle. however, if you're trying to EAS it doesn't take into account that nursing is a natural sleep inducer. i don't know of any breastfed baby who 1) eats on a schedule dictated by mama or 2) doesn't fall asleep at the breast.
this is my biggest issue w/ The Baby Whiperer (and BabyWise). it is completely unrealistic if you are hoping to establish a good solid nursing relationship- it doesn't really support breastfeeding and basically says that formula is a just as good an option as breast milk and merely a "personal choice".
(my experience with moms who swear by The Baby Whisperer and Babywise has also been highly annoying. the reality is they have had super mellow babies and/or they are "ok" with CIO which I am not. and interestingly, they all have been primarily formula fed.)