If the 'How did you come to find less wrong' thread is accurate, a lot of people came here through HPMoR. I'm not sure how many would have come if the HPMoR forums were elsewhere, but it seems like a non-negligible fraction of the community.
I got here through HPMoR, too, but not at all because of these discussions; I got here through Eliezer's links in the Author's Notes. Indeed, I had no idea this was the primary venue for MoR discussions until the link on hpmor.com made it obvious. I don't think it was very obviously linked to from anywhere on FFN before; or at least, I never saw it.
If we had dedicated forums, I think a series of banner "ads" ("Learn everything Rationalist Harry knows by reading the Sequences at Less Wrong", etc.), in addition to the frequent links to Mo...
The new discussion thread (part 15) is here.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 82. The previous thread passed 1000 comments as of the time of this writing, and so has long passed 500. Comment in the 13th thread until you read chapter 82.
There is now a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)
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: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13.
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: