Book of the year?

This is the book everyone has been talking about. Published today and there was lots of interest in it in waterstones today with lots of people sitting and reading it before deceiding to buy. The reviews havent been good though. Apparently Harper Lee didnt want to write another book after Mockingbird saying the only way after a book like that was down. Despite this having been written before Mockingbird it seems like expectation was high, despite in reality the book being a first draft of To Kill a Mockingbird.