I must state, this probably isn't the fairest review ever given but it is a fair warning. Like "student_in_love" mentions, this book highlights the differences between the sexes and so can provide many answers and a deeper insight into men...
However, proceed with caution.
I used to consider myself open minded and resonably comfortable in my own skin. When my current relationship started, I asked him for complete honesty. So I truly believed my partner loved me and took every word he said as truth. Until I read this book. I suddenly doubted his reassuring words of "I think only of you". With good reason, after I told him about all I'd learnt from this book, he confessed he'd been lying.
While this reflects more on my relationship than it does on this book, I believe it very important to point out that sometimes ignorance is bliss, Men and women are very different, but so is each individual person and their experiences. As such, it can be all too easy to discover truths that may not only shake your foundations but also haunt you endlessly.
If you are the jealous type, insecure or already in an shaky relationship, this book may do more harm than good.
Those who are single or have endless confidence will more than likely find it an entertaining and enlightening read.