I found I liked the first book best, which I gather is somewhat unusual. It was the cheeriest, the most archetypal (abused child found he's an important person in another world--the sequels has to have ambiguity and politics and such), and faster-moving than the later books.
I'm posting about HP now because I'd rather not have my notions lost in the immediate pre-Deathly Hallows mob of posts.
My expectations for the last book aren't complicated or detailed. Voldemort will be dead, dead, dead. Ok, there might be one horcrux unaccounted for. Dumbledore might show up to say "Well done", but he won't play an important part in the big fight. He *might* give a useful clue. I'm expecting Hermione to survive. Hogwarts won't be destroyed, but Slytherin might not make it. The House system might get undone--imho, it costs Hogwarts much more than it gives. It'd be nice to find out more about Ravenclaw, but I wouldn't count on it.
I'd like to see some resolution to the house elf subplot, but I'm not counting on that, either. Dumbledore says something about the wizards being responsible for the house elves' situation--I wonder what was going on there. Were they a magically powerful race enslaved mentally as well as physically?
Here's a theory for the fun of it: Snape is up to *lots*. Yes, he killed Dumbledore on Dumbledore's orders, but he rigged things so that Dumbledore would give those orders. Now Snape's planning to take over Voldemort's organization. His disgracefully bad Potions classes are part of the plot--if Hogwarts graduates were competent at potions, they'd be in a better position to undercut him.
Anyone have theories about why Dumbledore has such utter trust in Snape?
Addendum I don't care if Snape dies saving Harry, he's still a disgracefully bad teacher.
Another Addendum I'm expecting the Weasley twins to take an entertainingly chaotic part in the big fight. They might be sociopaths, or nearly so, but they're *our* sociopaths.