I say no because I don't want a walled garden. that just sounds so insane to me.
First, to be clear: I'm not saying break off from GAF for a different community, in case anyone thought that was my suggestion.
I agree and disagree, and I've been totally unable to come down on either side of the fence no matter how much thought I give the question. I've been a part of "walled garden" forums, and they can absolutely provide an environment that allows some people to feel comfortable being an active part of when they didn't feel that way with other online community.
At the same time, one of my most recent examples of trying to be part of such a community left me feeling like I had no interest in the place. What I found - and I guess I should have been smart enough to expect this - was that, at least at that forum, once you broke people down into "we're all here due to a common trail", they just found other reasons to group themselves off or create "us vs them" situations.
Human nature, I suppose.