About some oddball characters in a slightly altered version of New York City. There are some interesting parts in this book, but seems a little cutesy if you live in and are familiar with New York. I don't quite know what to make of it, to be honest. I wouldn't recommend it if you are on a beach somewhere, but I wouldn't discourage you from reading it if you are holed up in an air conditioned apartment and feeling sort of out of place in the world. The middle third of the book is pretty aggravating.
However, I would strongly recommend Lethem's graphic novel update of "Omega the Unknown." So there you have it.