That's not an easily definable answer. Almost every forum out there has a community. But not everybody enjoys every forum and community. From one member's standpoint, in their own home forum, their forum might be good. To another forum, that particular forum might be shit.
So what defines whether or not a forum is good? The overall perception of the community that calls it home. There is no "ideal" forum. Only the forum that you choose to call home.
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