The old ones got taken down because over time they splinter apart, people break off from an established forum and make a new forum that shares most of the same member base until it overtakes the old forum, etc. They are not so much getting taken down as they are evolving, changing admins, merging together, splintering apart, changing servers, etc. The life of a private forum tends to be fairly short, several months usually although in some cases a year or two. But the members all know each other and the groups kind of migrate together for the most part. For example, Sandoz Labs, a largely American / English Native community merged with The Bible, a largely European community with English as secondary language, when Bible was shut down many of the members went to RCN which then splintered off into FTWR which then turned into FTGB which then had someone on it splinter off into Su.pplier which broke apart into TLG, AFOYI and BBS (with the less trusted people on TLG and most trusted people on BBS), all three of which were shut down just prior to OVDB launching, which shut down but probably has a lot of members who joined SR after it went down. That is just one example of a migratory path. This shit has been going on for a decade now, with a lot of different 'original communities' and 'forum lines'. I am just naming one of many, the others I wouldn't want to name because they are not communities I had much of a role in. Another thing is that a lot of the really old forums have pretty much disintegrated due to lack of need, people talk with instant message programs now and have known each other for a long ass time. If you want something you just hit up one of your IM buddies and ask them to ask around for you. For example I don't even really need to be on any forums because I stay in regular touch with a lot of vendors who used to operate on forums. But there are definitely still a lot of private forums out there. I just don't really follow it much anymore. There are probably a lot more today than there were a few years ago even, over time the number of forums has always grown and I don't see why it would slow down really. Although one of the main phenomenon today is that people are on SR, so it is possible that SR kind of centralized everything to it. Instead of a noob forum starting and getting 100 members, then closing registration and another noob forum starting and getting 100 members, etc, all the noobs are just joining SR since it is so widely known and easily accessed.