Half Blood Prince didn't seem to have as many 'revelations' that OOTP did. But damn, it was quite a ride. I've only read it once so far so I may change my impressiona later on. But here it is:
Snape is a Goobad. We're sure he's good, we're sure he's bad. We dunno what to think. I haven't joined the Snape-is-Evil-and-Must-Be-Punished-Perferably-with-Very-Sharp-Objects camp. Color me crazy, but I think that the death of Dumbledore at Snape's hands was a set-up, which will play out in book seven. Dumbloedore himself would be the first to offer his own head as a sacrificial lamb, and in war would you rather lose a spy or a partially crippled general? Just a theory.
Fred and George's joke shop is successful. Yay twins! If Hogwarts remains open, it'd be a conenient way to get them to Hogsmede and closer to the school. But alas, it doesn't seem that there will be much of a school setting anyway does there?
Hagrid thankfully wasn't in the story much. His childish whining I outgrew in oh say the first half of SS.
The ministry's about face, and attempts to seduce Harry. I love the MoM, his honesty about what he wanted was refreshing. Makes one wish for it in certain, real life administrations.
Luna, bless her heart, that comentary of hers is one of my favorite scenes in the entire series.
In general, the 'maturing' relationships of those randy Gryffindors. Parts of them just felt completly forced and left me with a touch of nausea.
Hermione/Ron being shoved down our throats AGAIN. Oh dear lord, it makes me wish that they would just snog, realize that oposites don't always attract and get it over with already.
Tonks barely dragging herself out of the bed cause Remus is trying to be all nobel. That just didn't work for me. Hopefully some fic fleshing this stuff out will come out of this.
Harry/Ginny I like this, and it has potential, but it just seemed to come out of nowhere. Kind of reminded me of Harry/Cho which wasn't a good thing.
Horcrux. Tee hee! Hi, I'm 13 again.