I had to read it . The last title leaves the story hanging in mid air. This one too has a similar ending.
In any case we see Harry Potter much more mature here and Rowling playing to the fact that all the readers would have read her previous books cause there are extracts(not word to word) but yeah references to be made from the previous books.
I would suggest reading the older version before you read this.
The story remains non-linear and whenever you think you know whats happening you are wrong.
There are frustrating parts specially you would hate the new DATDA professor harry’s got and she has been made to llok so mean by rowling that you would like to shoot a bullet through the proffessors name.
The book is nothing like I’ve ever seen before or maybe nothing I’ll see more than 700 pages of reading makes you crazy and eager for more.
I really hope she satisfies everyones expectations with her next title Harry Potter and The Half Blood prince.