Okay, a very rough version of this is up.
Here's the basic idea:
from an individual movie page, there's a box to post a comment. If you use this it'll create a new thread, and that thread will be "attached" to that movie page, and not actually in the normal forums. There's a special forum called Specific Movie Threads that will hold them; they'll show up in searches, and New Posts, but the forum that holds them isn't on the forum home page.
If there are no such threads, the forum will simply search for similar-sounding threads and use those
until people create new ones, at which point it'll just use those. I'll probably fiddle so that it's transitional, so that if someone starts one thread from the movie page it doesn't just display the one, but "fills out" the other slots with the title search thing.
Example of a movie page with a thread "attached" to it (I cheated by adding one manually that's already existed awhile):
Joker.
Example of a movie page with no threads attached that displays its best guess at related threads in the meantime:
Taxi Driver.
Small by itself, but I'm going to change some other stuff to re-orient the site more towards those movie pages. This'll probably not change too much for anyone who likes the site the way it is. Most likely next step is just putting new releases at the top of a new home page so people can quickly find a way to talk about something they just saw.
Let me know if you guys find any issues or bugs.
Very much an ongoing process...