Update: Discussion has moved on to a new thread.
The hiatus is over with today's publication of chapter 73, and the previous thread is approaching the 500-comment threshold, so let's start a new Harry Potter and the Methods of Rationality discussion thread. This is the place to discuss Eliezer Yudkowsky's Harry Potter fanfic and anything related to it.
The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system. Also: one, two, three, four, five, six, seven. The fanfiction.net author page is the central location for information about updates and links to HPMOR-related goodies, and AdeleneDawner has kept an archive of Author's Notes.
As a reminder, it's often useful to start your comment by indicating which chapter you are commenting on.
Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically:
You do not need to rot13 anything about HP:MoR or the original Harry Potter series unless you are posting insider information from Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).
If there is evidence for X in MOR and/or canon then it's fine to post about X without rot13, even if you also have heard privately from Eliezer that X is true. But you should not post that "Eliezer said X is true" unless you use rot13.
Gah? Seriously? WTF did they change that? That's arbitrary.
I somehow lost interest in the movies after about 3 or so. Not sure why. Possibly because Ginny wasn't nearly as cute or as sane as in the books and possibly because I just didn't want to see Ron's face or hear him say stupid, stupid things.
Well I suppose destroying it is possibly less insane than leaving it with Dumbledore where anyone would look. Just not as sane as keeping it, being badass and cough "optimising" the world.
Because he wanted nobody else to have it, and frankly the book solution of "I'll hide it, and hope nobody finds it again" was extremely inadequate; especially after dozens of people had heard Voldemort and Harry discuss its existence.
The movie version of snapping it in two and throwing it away made the point much louder and much more finally.