As suggested over in the Worm discussion thread, let's try having a discussion thread for Wildbow's new web fiction, Pact.
Just to get things started, and since this site is officially dedicated to the Authorlord's many fine fanfics - including Harry Potter - how do you think the sorcery of the Potterverse would mesh with Pactworld's magic?
For that matter, Wildbow made some sly allusions to Rowling's stories in one of the interlude chapters, where it was mentioned that British Practitioners favored wands as their implements.
The idea of a Harry Potter/Pact crossover fanfic seems rather appealing; the young wizards and witches at Hogwarts started out relatively innocent and naïve of the grim inner workings of the world, much like the youngest Practitioners in Pact have been shown to act. Gradually, over the course of the books, Harry & friends were introduced to the darker side of life, which would probably be a much more accelerated process if the HP stories were set in the world of Pact.
Also, in a HP/Pact crossover, you could theoretically get an Acromantula or a Norwegian Ridgeback as your Familiar. It also raises some interesting questions about House Elves - in an HP/Pact crossover, would they be Familiars or a form of perambulatory extension of the Practitioner's Demesne?
EDIT: Oh, and by the way, even though people commenting here will no doubt do their best to use spoiler tags to avoid ruining things for new readers, be warned that some things might slip. If you want to completely avoid spoilers, it's probably best to read the story all the way to its most recent chapter first.
PS: This might be tooting my own horn a little, but if you're interested in Pact fan drawings, check out the Blakeguard group on DeviantArt.