I finished it this morning. When I was about a hundred pages from the ending, I found that I couldn't stop.
I think that this book, even more than the others, is a coming-of-age story. What happens when the elders you trust don't have all the answers, can't protect you anymore? I thought it was well-done.
Also, at this point I'm feeling curious about where Rowling will go next with the series. It seems as though this was the last Hogwarts' book. But not the last book in the series. I can imagine there being one more book, and then related series... or one more book for each aspect of Voldemort still alive.
Similarly, I'm wondering if there will be a further explanation of why Dumbledore went so far in trusting Snape.
Anyway, it was really good. If it's your sort of thing, read it.