Agreed. They made it even worse by cutting the World Cup Final from the fourth movie, although there at least it makes some sense as it would take the pace out of things. I think this is largely thanks to Cuaron not being so interested in it and wanting to focus more on the teenagers and their feelings... he's done some excellent stuff, including the aforementioned Slap, but yeah, it's a shame to lose the Quidditch.

Yeah, this is a short return to children's book land, I would say... the icing on the cake, making things as perfect for a short moment as at the end of book one with Dumbledore handing out those points (and, as Jonte argued, completely messing up the concept of the House Cup in the process).

Those are great, alright.

About the Dementors? I guess... she just wanted to make clear he was on a high, I suppose.

As I recall Dumbledore's comments in book six, what is most Horcrux about the diary is that Riddle can project himself out of it. The communicating with him through the diary isn't so unusual, evidently, and I agree that the Marauders must've done something similar. The map definitely wouldn't have reacted like that to others.

Yeah, there are a few times in the books, including here, where you have to say Harry gets off strangely lightly when you expect Snape to throw the book at him. Perhaps Snape is afraid Dumbledore will overrule him if he can't genuinely prove Harry is guilty. Or perhaps he just isn't as much of an ass as he is in the classroom, where he uses his mean wit and unfair punishments to keep order and discipline (we've all had teachers like that, I'm sure).