So is this some sort of glitch in predictionbook which falsely records me editing the prediction, when in reality it was edited by some moderator?
Yes, that was gwern. The site doesn't keep track of who changed the prediction, so it just assumes the author of the prediction ( = you) did it.
(The sheer amount of "they just didn't care" inherent in the site design boggles the mind.)
Though rarely updated, PredictionBook is open source. So at least you don't have to wait for the creators to fix it, if you know how to code. I wrote up an Issue for this bug, describing some starting points for fixing it.
The recent spate of updates has reminded me that while each chapter is enjoyable, the approaching end of MoR, as awesome as it no doubt will be, also means the end of our ability to learn from predicting the truth of the MoR-verse and its future.
With that in mind, I have compiled a page of predictions on sundry topics, much like my other page on predictions for Neon Genesis Evangelion; I encourage people to suggest plausible predictions that I've omitted, register their probabilities on PredictionBook.com, and come up with their own predictions. Then we can all look back when MoR finishes and reflect on what we (or Eliezer) did poorly or well.
The page is currently up to >182 predictions.