I started reading this book with a bias against it. In Steven Pinker's The Better Angels of Our Nature, Steven debunks the most provocative claim of Freakonomics - that legalized abortion int he '70s led to a decrease in crime in NYC in the '90s. So I was somewhat skeptical of the rest of the statistics cited.
I was especially skeptical when the author stated that baby names have nothing to do with the success of the child. I've read research, for instance, that said children with the name Lawrence have a higher probability of becoming lawyers and children with the name Dennis have a higher probability of becoming dentists. No one knows why. To be fair, these facts don't negate all facts presented in this book, so I tried to keep my mind open.
Even though statistics can be manipulated, the fact that Steven Levitt helped identify cheating teachers who purposely falsified test scores in the Chicago public school system is indisputable. His reputation among economists is solid, and I do like the idea of finding hidden meaning in statistical patterns - some truly mind-blowing things have been discovered (read my review of Scale for an example). Still, I wouldn't recommend reading the whole book.
There was way too much time devoted to statistics of baby names. The audio book spent a great deal of time promoting Steven Levitt himself., which I found off-putting. And, as I mentioned previously, several of the theories in the book are questionable.
If you'd like a good introduction into what statistical analysis can accomplish, then go ahead and take a read (or listen). But if you already know, then don't bother.