Take my advice, since I've been running a similar social community for almost 1 and 1/2 years: Niche fishing forum is the way to go, or at least the way to start. It is much easier to get a niche targeted community off the ground than a general interest one. You can always expand a growing community with a good foundation. Working on a niche group would make growth a lot faster, and when you have attained a good spot, that would be a good time to expand. General forums are extremely hard to maintain. The only thing I can say is work on getting content, treat every new member like your only member, and advertise everywhere.
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