|Title||First Print Run (US/UK)||First Day Sales|
|Chamber of Secrets||250K/10K|
|Prisoner of Azkaban||500K||68K (UK)|
|Goblet of Fire||3.8M/>1.2M||373K (UK)|
|Order of the Phoenix||6.8M||5M (US), 1.8M (UK)|
|Halfblood Prince||10.8M||6.9M (US)|
|Deathly Hallows||12M||8.3M (US)|
Of course, it's likely that more than 20M copies have since been printed of each volume, but those are the initial print runs of each book. For fantasy books, each of those after the first two or three are absurdly large. The sixth and seventh each set the record for largest initial print run (not just for fantasy; for all books).
Getting back to the movie, after the slight disappointment of the fourth, and great disappointment of the fifth, I haven't watched the sixth or seventh, and am unlikely to watch the latest.
Thanks to a fan-fiction I've been reading the last few days, though, I'm probably going to re-read the books sometime fairly soon. After the latest Dresden novel, which I just got the shipping notice on. But my point in bringing up the Harry Potter re-reading is that I'll probably try to collect a lot of thoughts about the series when I do so. (Assuming that it doesn't get pushed back as badly as Riordan's Lost Hero, which I read six or eight months ago.)
To give a little bit about the fan-fic, it's conceived as what would happen if his step-mom Petunia had ended up marrying a scientist instead of Dursley. It's a bit more than that, though, as Harry is much smarter and more mature than in the original, and some of the other characters have changed as well.
I'm enjoying reading it, although I wish the author would skip all the fourth-wall breakage that's in there. The one good thing about it is that it's more subtle than having a character speak directly to the audience, but there's way too much of it. That sort of thing can work in a spoof or farce, but just doesn't work in anything more serious (in fact, it'll frequently get me to stop reading online stories immediately). It hasn't ruined the story (which is very funny), but has made it harder to read.
I'm not sure if I can describe exactly how, but the story is kind of the physicist's counterpart to Leo Frankowski's Conrad Stargard series (which is definitely written for engineers), into which magic is thrown. Plus, Harry is able to win verbal battles with adults in ways that just aren't going to happen in real life.
But I've read up to about chapter forty, so there's definitely some good stuff going on in there as well. There's even a podcast of it being read, which is also good, but I wasn't going to wait on that.