Here's my take:
The only thing that really and truly surprised me about Harry Potter 7 was that Ginny almost gave Harry her virginity.
I was also rather pissed about the Muggle Studies professor getting a name. Dammit.
On the whole, I was very pleased, but toward the middle, Rowling pulled a Laurell K. Hamilton. In the three Anita Blake books before "The Harlequin", which was very good, Hamilton basically pulls new powers for Anita out of thin air. It's like, oops, now she's even more powerful because of x, y, or z. Well, the Deathly Hallows are the same way. All of a sudden, Harry learns about this power that could rival Horcruxes. A little frustrating.
Also, the penultimate chapter was kind of upsetting in that I felt it was almost too much deus ex machina. When you go back through Star Wars I-III, you see where Lucas laid in bits to lead to IV-VI. In HP7, you get paid back for almost every seemingly useless detail of the past five books. But you also have to keep track of all of it. The whole thing where "Dumbledore" explains to Harry what just happened..? Come on.
I also think Chapter 35 totally cheapened Harry's sacrifice.
How I think it should have ended, before I even read HP7: Harry and Voldemort fight. Voldemort mortally wounds Harry in Snape's presence, and Harry survives just long enough to see Snape kill Voldemort. But since Harry was the only witness to it, no one but the reader knows Snape really wasn't evil.
And then, what I think should have happened after Chapter 34: After Voldemort kills Harry -- really kills him -- he goes back to the school, fully intent on breaking his word and subjugating everyone who stood against him. Chapter 35 is nonexistent. Back at the school, all the same stuff happens except that Harry doesn't wake up. Also, we see that Neville has some sort of curse mark on him -- like, on his arm or something -- that he gets while fighting the Death Eaters. He kills Nagini, like Harry said he should, and then takes out Voldemort. They explain that his birthday was also July 31, and his parents thrice defied Voldemort, and look, here's a mark to mark him as his equal.
And finally... all that wandlore stuff felt to me like Rowling had written herself into a bit of a corner and needed a way out.
All that being said, I actually did like the book quite a lot. I had a few HA! moments, and for a second I was actually afraid that some fanfic would come true in that Snape and Lily were good friends until the end of 5th year, and I was kind of worried that they'd reconcile and we'd see that Snape was really Harry's father.
Overall, I think the book lived up to the hype, which is very high praise given just how much hype there was.
My friend Holly said she thinks HP7 is a very visual book that will play well as a film -- although I think it will have to be almost three full hours long, maybe even more -- but she worries that HP6 is so talky that huge chunks of it will be cut out so as not to bore people.
