Here are my thoughts. SPOILERS, obviously. I'm turning this white for readers of the blog itself, but RSS readers beware! Highlight to read...
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1) I can't say that I "called" the "Harry is a horcrux" thing, because I heard that idea from someone else right after #6 came out, but that was definitely my pet theory from the moment I heard it, so yeah, not too surprising.
2) I felt this way about the introduction of the horcrux concept in #6: Didn't the sudden, quest-defining emphasis on the Hallows in general, wandlore, and Dumbledore's family come in a little late in the game? It's a little like if the Ring didn't enter into the picture until The Return of the King. This goes double for all the business about taking control of the Elder Wand around which the climax revolved--I had to reread the final spell vs. spell section three times just to figure out what was going on.
3) It was interesting how the books' usual emphasis on adult characters not believing Harry was shifted to Harry's friends not believing Harry. It wasn't hit quite as hard as usual, but still.
4) The book really got bogged down in the section where Harry, Hermione, and Ron got bogged down.
5) Fred, Tonks, Lupin, Dobby, Scrimgeour, Mad-Eye, Hedwig? Kind of redshirt-y. Snape and Voldemort are big deals, of course, but also kind of expected (and in Voldemort's case, guaranteed).
6) There was a TON of interesting stuff that never got wrapped up. Did Dolores Umbridge and Rita Skeever ever get their comeuppance? Did the Wizarding community wake up to its frequently cruel treatment of other races and creatures, as the house-elf, dragon, and goblin subplots seemed to be leading to? What became of the giants, spiders, centaurs, goblins, house-elves, dementors and other creatures that got involved in the war? What happened to the Slytherin students whose retreat from Hogwart's Voldemort viewed as evidence that they were on his side? What was the emotional effect the battle had on our main characters?
7) Instead of any of that, we get this superfluous, series-finale-style "19 years later" epilogue, which reveals the fascinating facts that Harry & Ginny and Ron & Hermione got married and named their kids after characters they loved. Well blow me down.
EDITED TO ADD:
8) She's definitely not writing with the movies in mind, considering how frequently the lead characters go through major scenes while transfigured or disfigured.
9) Clearly she's also not a believer in "show, don't tell." For example, the ENTIRE Albus/Aberforth/Ariana/whatsisface-the-dark-wizard storyline was TOLD to Harry, rather than unfolding in a way that involved Harry as an active participant. Strange.
So, enjoyable, but disappointing.