I'm a sucker for coming-of-age novels written by people about my age. Jonathan Lethem is from Brooklyn and I'm from Queens, so my fondness for this book is perhaps axiomatic. The first half of the book is a coming of age story; the second, more of a quest: to find the lost best friend and the lost mother.
I found the first half stronger, but maybe I simply related to it more. Throughout, there is terrific writing.
The superhero subplot felt extraneous; I kept wanting more to come of it.