Here's what I feel. I think it's a great idea for clubs to have their own forums. It could be a good place for them to communicate club info, especially if they are smaller and don't have a website.
However, I do feel opposed to the idea of these forums being private. I think that that inhibits the general mindset of lighthouse communities being open to all. Plus, if this were the club's only online outlet, then I wouldn't want it to be closed to non-club members.
I feel that it's a great idea to give clubs their own forums. I know that if I ever form Tri-State Lighthousers, a trip-oriented club for people in the NYC metro area, then I would definitely want us to have a CF outlet. But I would also want our forum open to all members of the CF. I feel that the same results can be had by clubs with a public forum. As you said before John (and not meaning to be obnoxious by quoting, but rather to repeat something that I think really describes the CF as a whole), "All for One and One for All."
That's the end of my solicited true opinion.