I liked this book, but not as much as I thought I would. A lot of the material has been given full length treatments now in similar books. For example, if you want to learn more about the affects of birth order, Malcom Gladwell's Outliers: The Story of Success is a more comprehensive take on it. However, Quirkology does serve as a great introduction to the subject.
I love books that deal with this type of behavioral economics or odd psychological principles, but can't seem to get very many others interested in them. If someone asked me for a recommendation on the subject now, this would be one of the top two I would suggest to them. It's fast paced, packed with information, and can easily lead to more reading. There was definitely some new information here, but not as much as I expected.
Some of things I learned include what drawing a Q on your forehead means about your lying ability, whether people would wear a sweater once owned by a mass murderer, and how to double your panhandling intake with one phrase. There is a ton of information here, and its really great stuff. Well worth your time.