Whew. What a ride. This was actually my favorite book in the series. I thought it really picked up as it went along, and the pace matched the growing sense of urgency about Voldemort and the upcoming battle-of-battles. Everyone was there at the end, and it was just a great, epic climax.
Along the way, I kept noticing all the perfect gaps for fanfic writers to fill in; I can see the trove of "Trio's lonely nights in the woods/ Hermione/Harry's lonely nights in the woods/etc" that will inevitably pop up, and Remus' unhappiness will undoubtedly be looked at as pining for Sirius and the life they could've had together (I'm choosing that view as well).
Favorite points:
Snape redeemed! I'm really not a fan of Lily/Snape ships, and have avoided fanfics like the plague that alluded to them over the years, but getting to see Snape's history felt really right and satisfying, and I'm a fan of the friendship they had, and how it fell apart (but I'm glad the romantic feelings seemed to be unrequited; I just can't see them together.) I was betting on Snape killing Dumbledore on Dumbledore's orders, but I wasn't expecting such detailed fill-in-the-blanks, so that was really cool.
Dumbledore! Much more interesting that I had anticipated, and I'm glad that, on the whole, he was a good guy.
I cried and cried and cried as Harry marched to his death, I really did. With his parents and the *sniffle* whole thing. Cry cry cry.
On the misc deaths/savings: Draco being alive, I liked. Narcissa helping Harry because he helped Draco, I really loved. The Malfoys redeeming themselves was not something I anticipated at all, but it was nice. Tonks and Lupin seemed kind of pointless deaths, Hagrid lived, yay! Oh, and poor Fred. :( Poor George - what's he gonna do without his brother?
Horcruxes or Hallows? Cool plot. Harry as the 7th Horcrux fit well, and it was interesting myth and history.
Neville! And the whole Hogwarts subplot - I loved that we got to see that while Harry and the gang were away, there was a whole slew of horrors going on at Hogwarts, and Neville was taking the lead.
Luna. I love her more than anyone, I think.
Less than favorite things - Ron running off because they got in an argument seemed weird. Didn't they learn anything from the last six books? I guess it was necessary so Ron could rush back and have his moment saving Harry and slicing the Horcrux, but I still found it odd that Ron would just throw a tantrum and run off.
How did Neville get the sword at the end? I must've missed that.