I managed to read this in just a few days as well and found it fascinating. It wasn't quite what I expected....actually it was nothing like I expected but it did put forth a couple of thought provoking ideas.
Levitt is a well respected economics prodigy and Dubner is a journalistic friend who thought he could help Levitt tell his story and explain his theories to the masses.
The theory that legalised abortion caused the remarkable reduction in crime rates in the early 90s is perhaps one of the most controversial. The discussion of corruption amongst sumo wrestlers is a somewhat amusing but how this technique was used to eliminate cheating teachers from the Chicago school system was inspirational. It is a shame that the theory about how the KKK was brought down proved later to be based on an urban myth but hey, when your data set is flawed, what's an economist to do?
One of the authors' objectives in writing this book was not so much to prove or disprove various correlations between data sets but more to get people questioning conventional wisdom and asking the right questions.
This is was most certainly a fascinating read. And it only takes a few short hours to get all the way through it. I recommend it if you are willing to look at the world from a different perspective.