Colin Singleton has just been dumped by his 19th Katherine. In the throes of breakup despair, he is dragged on a (very short) road trip by his friend, Hassan, that lands the pair of them in Gunshot, Tennessee. 
 I felt that Abundance lacked a lot of the strength and consequence of Green's other books. The "eureka moment" (essentially an epiphany) at the end followed by a multi-page lecture about the nature of the future and relationships and mattering was excessive and pedantic. 
 Other than that, I enjoyed the book. Like most of Green's writing, I could see myself in his characters. I was never a prodigy, but I was "smart," and I knew exactly what Colin is talking about when he reaches adulthood and, suddenly, the party trick intelligence that got him so much as a child suddenly doesn't matter any more. I also could understand Lindsey's end-teen search for identity. As for Hassan, I was friends with him (except he was Serbian and Eastern Orthodox). 
 While Hassan didn't strike me as a stereotype because I knew him, I do see what people mean when they complain about his weight being such a feature of the story. As an "exotic," it's a bit of a cliche to make him physically unappealing so that he is not a threat to the heterosexual white male. 
 I've now read all of John Green's books (not counting Will Grayson, Will Grayson, which was written with a co-author), and I have to put Abundance at the bottom of the list. That doesn't make it bad - it was still a fun read, very funny, and contained plenty of the trivia I do so love - but it's certainly the weakest of his oeuvre.