Agreed. There were indications before that Malfoy wasn't entirely as Harry saw him, but these few paragraphs here completely alter our view of his character (well, okay, not ours because we knew it was coming, but that of the new reader). Draco's reaction mirrors that of his mother early in the book in terms of lashing out to hide his pain from outsiders, but there are limits to his self-control so he can't do so coldly and calmly as no doubt he'd like to do. And it's tempting to see the influence of aunt Bellatrix - who he must have been distancing himself from over the course of the year as he starts to realize he's really not cut out to be a DE - resurface in his attempted use of the Cruciatus.

What's interesting is that Draco mentions that "unless I do it soon, he says he'll kill me". That's even worse than what Narcissa had been fearing early on in the book - which was that Draco would die trying, one supposes by the hand of Dumbledore (which also makes one wonder just how badly Narcissa knows Dumbledore, but I digress). It's also a bizarre kind of threat, something that as far as I'm aware we don't see Voldemort telling anyone else. It would have made far more sense if he'd said "unless I do it soon, he'll kill my father", but no. Strange.

And on the topic of the Cruciatus, it does make psychological sense in the scene, but still in a way it's Rowling letting Harry off easy. He had been intending to use Sectumsempra on an "enemy" who annoyed or irritated him, which would've essentially been unprovoked attempted murder, but now ends up merely doing it in reaction to an Unforgiveable curse. The result still shakes him up rather badly, but it's a far cry from what it would've been if he had done it to McLaggen for nagging at him, or to Draco during an exchange of more innocent hexes.

It's a good lesson to Harry on the meaning of the word "enemy", though. Evidently, Snape has rather more serious enemies as a schoolboy than just people annoying him, or at least expects to have such serious enemies in the future.

She definitely knows - he did give her a few hints even apart from his wandering eyes. Hermione's gloating over Ron and Lavender breaking up is a tad mean, but understandable.

It is rather heartless to abuse Hagrid's confidence so, though on the other hand he does show his worth in exchange, by doing the little speech and joining Hagrid in his drinking binge. His prejudices show again in the memory scene (the "decent wizarding stock" remark), and again with the house elves thing. Quite grey character, yes.

He is, isn't he? Especially considering how he wanted Harry expelled in earlier books - this is his best chance yet. I think we have to conclude he realizes it's too dangerous to expel Harry at this point.

He so knows about the HBP book thing, now. Or suspects, at least.

What I like about Harry there is that he doesn't look for excuses. He does of course say that he didn't know what the spell would do, but he doesn't mention the Cruciatus at all, nor does he use that as an excuse to justify his action to himself.

I think it just means she's determined.