Photo.net is in the business of being everything for everybody, as a result, it isn't really good for any one specific area of interest. I'm still a photo.net subscriber (I'm current until sometime in 2006), but I won't renew once my membership there runs out.
I almost became a subscriber to photosig.com, but the moderators of that site tend to be too heavy handed, and it's real rare for a good, down in the weeds type discussion of analog technique.
f/32.net doesn't seem to have anyone in charge, or at least anyone who will answer an email.
The largeformatphotography.info forums are sort of a break off of the large format forum on photo.net and, after APUG, is my second choice of a place for photo discussions.
There are a few others as well, but all in all, I avoid ANY site that has a points rating systems for members (such as photosig).