He-Who-Must-Not-Be Named is on the loose and is practically unstoppable at this point. He also took special interest in killing Harry Potter whose main mission for the book would be not to die long enough to fulfill the mission given to him by Dumbledore in the previous book, thus no Hogwarts studies this time; it is about stayin' alive for Harry:
Something I noticed again during my reread of the series, especially this book: J.K. Rowling is not at all shy about killing her characters, especially good ones. George R.R. Martin often gets all the slack for doing this
but despite Harry Potter's author saying that she feels bad about killing good people, a great number of them died in the series (and outside it if you start counting from Harry's parents). Some of these deaths are still as tragic on the second time around.
Harry's gradual discovery of Dumbledore as not-quite-good-guy is brilliant. It took me two reads to grasp all the nuances of this.
Now for the bad parts which unfortunately made me reduce otherwise perfect rating by one star. Ron - to use his favorite word - is a git, especially in this book. He was destined to remain forever in Harry's shadow, but this is exactly the place he deserved. He did not do anything exciting on his own since fated chess match in the first (!) book.
As a character Ginny Weasley cannot be even compared to Luna Lovegood, not to mention Hermione Granger. If Harry could not get Hermione, I hoped he ended up with Luna - sure she is loony at times, but she is always understanding, brave, and smart; read carefully her parts if you do not believe me. She was able to help Harry more than Ginny whose only help was kissing him a couple of times.
The forest sequence of the book was way too long. This is probably the only part of the series which felt drown out. The whole epilogue feels off. I understand the need to show happily ever after
but it still feels out of place.
So as I mentioned with these complaints I have to reduce the rating by one, reluctantly. The whole series however deserved unconditional perfect rating. If you have not read it because you think this is for children or because it is too mainstream, or because you think it offends your religious beliefs - get off your high horse
and head to your nearest library for the magical experience.