My wife and I finished the latest last night. I must disagree with the detractors. I found it tightly organized and well controlled. A certain flabbiness in conversation, external and internal, that I had seen in the last volume has been reined in.
The interest of this is psychological. You might call it Voldemort’s psychoanalysis. You should also think of Sun Tzu, know the mind of your enemy. The climax, of course, reveals a great irony in that.
Rowling has set herself a harder task for the finisher. Harry will have to bear a greater weight of the action and the thinking.
Plot point to watch for: Wormtail (Dumbledore had a thought about him one or two volumes back).