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Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).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.
I donated, because it was a good reminder that I should be donating anyway, but the reward kind of leaves me cold. If Eliezer writes new chapters after 78 at a constant rate while publishing existing chapters, then if he publishes all his existing chapters really quickly he won't get many new chapters done in the interim and we'll have to wait a longer time after 78 for 79. If he publishes existing chapters slowly, he'll have 79 done by the time he gets to 78, and can publish those at a steady rate while working on 80+.
So instead of donating to get more total HPatMOR, donations change the pacing away from "slow and steady" and toward "quick burst of chapters now, then a longer interval", with the end date of the fic not changing at all. Personally, I would prefer the steadier pacing.
For human-psychological reasons I expect that "the drive to complete more chapters" will become appreciable pretty much the moment 78 is published (and not much before).
Even if I am wrong, I don't think "writes at a constant rate" is a safe assumption to make about Eliezer's fiction writing. (This is, of course, tongue in cheek.)