Some of COW's staff and membership have contacts with Ford, Lucas, Spielberg, etc; and members like Tony Nowak and Steve Delk, who is a frequent poster there, made jackets and hats for the films. In that sense, COW might be a little more like an exclusive club, but as far as I know, anyone who wants to can still join.
For some reason, the endless debates over tiny, tiny details there that I used to find fascinating have become a bit tiresome for me; other than that, it's a great forum and without a doubt the best resource for anyone engaged in research on Indy's costume.
Jack