Hey there, campers.
The venerable gearslutz.com has recently added a forum specific to audio post. While there are other forums out there (most notably the Digidesign User Conference, or D.U.C.), they are mostly product-oriented, whereas this one is just about audio post in general.
In addition to her day job at Global Audio, Georgia Hilton, M.P.S.E., C.A.S., has posted quite a bit of good info over there about the history of audio post, as well as a guide to industry terminology, so be sure to check those out.
Link to gearslutz post forum.
(Note: don't be confused by the website's name. Anyone expecting to see scantily clad women draped in microphone cables will be sorely disappointed :)