Spoilers, spoilers, spoilers.
Having finished the book, i still think it wasn't so much dark as realistic. Prisoner of Azkaban was dark. Now however Voldemort is out in the open, even if most people refuse to accept that for the majority of the book. Things are certainly _dangerous_ and can get a bit depressing at times, but i wouldn't really call it dark.
I have the suspicion that J.K. Rowling was a bit of a tease. She knew that everyone would know about the death, and she had fun putting everyone she could in harms way right up till the end. The closer it got to the end, the more serious the harm and the more the implication that the person might be dead/killed. If she was intentionally doing that, i'm not sure how fair a literary technique it is. Using in-book techniques to clue in the readers that someone is going to die and then taking advantage of that knowledge is fine, i'm not so sure about using your massive fanbase as a publicity tool to do so.
That having been said, i'm not sure what to think about Sirius' death. In some sense it didn't fulfil the emotional expectations we normally hold for death in dramatic circumstances. However like a lot of the rest of the book, it was very real. When people die, especially in the middle of battle, it is sometimes just a matter of there one second and dead the next, and although it was certainly facilitated by the vanishing act, Harry's reaction was fairly realistic.
I'm not so sure about Harry's reactions to Snape on the other hand. Leora, i don't think that was supposed to be Snape's _worst_ memory, although maybe i missed something saying it was. It was certainl a bad memory, and quite possibly one of his most _embaressing_ memories, although given what was said it sounds like it may well have been fairly normal for that time period.
I think however that the importance was not so much how bad it was for Snape, but the fact that Snape had fairly good reasons for hating James Potter, and by illogical extension, Harry. That being that James was a total asshole. Knowing that they had been in conflict earlier is _very_ different from knowing that James was an arrogant jerk about it, and might well have started the whole thing. I think _that_ was the important revelation we were supposed to get, and i was kind of suprised, and it certainly had an effect on Harry. He's been told that his dad was a bit of a rebel, but he'd always imagined that in terms of Fred and George. Instead it was rather more like Malfoy.
At that point, i think Harry really owed Snape an apology. Both for the snoping around and... i guess for the assumptions he made? Not exactly a sins of the father type thing, but showing sympathy for him and regret that those past actions had made things so difficult between them now.
I don't really understand Harry's reaction to Snape at the end. I need to reread that section, but his suddenly renewed hatred for Snape certainly doesn't make any logical sense, and it doesn't make much emotional sense either. Perhaps blaming Snape was easier than accepting who was really responsible? Namely, himself and Dumbledore, and to some extent Sirius for being so reckless.
One thing i'm wondering, why did J.K. Rowling miss such an obvious opportunity to exploit more angst with the mirror? Why didn't Harry realize that he had never tried that mathod of getting in contact with Sirius when he thought he was in danger? Having Harry realize that he had had a way to contact Sirius the entire time and avoid falling into the trap and thus getting Sirius killed seems like too good of material to pass up.
I really liked Ron's reaction to Ginny's love life :) I don't really understand Harry's cluelessness about girls, or at least not his particular variety. As far back as i can remember, i never had any trouble considering that a girl might be interested in me or be asking me out or whatever. I was perfectly happy to recognize anything that even hinted at that, and then spend forever agonizing over whether she really meant that, or i was just imagining it, or what. However i never was so clueless as to not even think of the possibility. However such a state has been described in enough detail in enough different sources that i have to accept it's strange existance in a large part of the population.
Other than for the girl issues, Harry acted like an idiot a lot, but usually in the was in ways you'd expect a 15 year old to act like an idiot, and the same with everyone else.
Oh, I'm also wondering if part of the plot for this book was influenced by certain recent events in America and the American media.
Why is everyone convinced that the prophecy is such a gimme? Convinced that it's so meaningless?
As usual. my memory of specific details is hazy, so if i get anything wrong feel free to correct me, but;
From the very begining, we were given the impression that Voldemort was going around and randomly killing anyone who tried to resist him. He get's to the Potter's house, kills James, kills Lily, and then out of the blue when he tries to finish off the last member of the family, his spell backfires and kills him. We have no clue how it happened, but it seems like a completly random event.
We then learn that Voldemort isn't quite dead and is trying to come back. Harry hates him because of the murder of his parents, and the semi-psychic link between them through the scar enables him to do more than most to try and stop Voldemort. Likewise, Vodlemort hates Harry for having killed him. When Voldemort actually does come back to life, it is through a ceremony that involves the person who killed him, so given the failure of the earlier attempts, Harry was necessary for Voldemort's purposes.
After that however, why should Harry matter much anymore in the fight with Voldemort? His psychic link was usefull, but it's become as much of a liability as an asset, and unless he can somehow discover what happened when he was a baby, he wouldn't seem to be that much more important in the fight against Voldemort than anyone else. Sure he's driven on by hatred, but a lot of people lost a lot of relatives, so he's certainly not the only one.
Clearly from a story perspective we want Harry to be the one to defeat Voldemort, but there's no compelling reason to suggest that he has to be the one to do it, or that he has particularly better odds than Dumbledore. On the bright side however, that means that Harry is in some sense relieved of the responsibility. At any moment some other member of the Order of the Phoenix might get lucky and take Voldemort out, and Harry wouldn't have to lift a finger.
What The Prophecy says however is that it was _not_ accident that Voldemort was defeated by Harry back then, and that it was _not_ accident that Voldemort had tracked down James and Lily rather than some other member of the old Order of the Phoenix.
We started out not knowing why or how Harry first defeated Voldemort, the how is still very murky, but we know _why_ it happened now.
Cause and effect has been completly reversed from what we were lead to believe at the begining of the series. Harry was (50/50) predestined to defeat Vodlemort before he was even born. As much as the prophecy is a boon to everyone else in that it provides a semi-specific way for Voldemort to be defeated, it's really a doom for Harry. It killed his parents, and it has doomed him to face off against Voldemort. Up until the prophecy was revealed he could always hope that someone else would finish off Voldemort for him. Even if he decided to say to hell with the rest of the world and try to escape, the prophecy almost guarantees that Voldemort would do his best to hunt him down. Before he could have entertained the notion that now that Voldemort was back his interest in Harry was greatly reduced.
Of course the prophecy _does_ provide a slight out, although i don't expect it to happen. It doesn't say that it will be the _first_ one marked, only that they will be marked. And regardless, it does indicate that the other may be quite a bit more important than they first seemed.