Freakonomics

I don't get what all the hype is about for Steven Levitt and Stephen Dubner's Freakonomics. For the most part, it was all stuff I'd heard before. I'd positive I've sections of it elsewhere as is likely since a lot of the stuff was previously published. I'm sure I've seen some of the stuff in course packs... I know I've read the stuff about the Black Disciples before. It was interesting enough I suppose. But I don't get what all the hype is about. And I'm still not positive how it's all economics...