I can't believe how many people think Order is the worst book. OK the stuff with the giants and Grawp was overkill from JKR but the rest of it is brilliant. It totally blew me away when I first read it. I mean, the series had obviously been fantastic up to this point, but this was something else. Everything about the Ministry, the Prophecy, the veil, the part in the hospital with Neville's parents, the Dementor opening, Grimmauld Place etc. was much bigger than anything so far.
I still think The Lost Prophecy is the best chapter Jo has ever written...er, no, second best chapter, the best is The Forest Again in Deathly Hallows! It was obvious that she deliberately went less in-depth with Half-Blood Prince to make it shorter for everyone who whined. And aside from giving us more background about Voldemort there wasn't much more story for her to tell as it had to be saved for the last book. I thought the parts with Harry being obsessed with Ginny were pretty weak, and Hermione/Ron. The Draco mystery was boring too. The story was nothing like as masterful as it had been for Order, Goblet of Fire and Prisoner of Azkaban. It was a good job the end was up to scratch or else I might rate it the weakest of all 7!