This is my favorite kind of book. There is a plot, although it is not readily apparent. The reader kind of has to figure out what it was at the end.
The book is about the characters: the most interesting collection of characters I've encountered in a long time. Each one is a totally believable and "real" person, while being completely unique, quirky and even occasionally bizarre.
There is no way to describe this book without spoilers, so I won't try.
All I can say is: READ THIS BOOK! The writing is amazing.