RPG theory time, kiddies! Ron Edwards closed the GNS worship section of the Forge, so someone has to pick up the slack. As we all know, every good RPG theory has to divide all games into several vague categories. My categories are Retro, Stupid, and Pretentious. Any RPG worth playing will fall into one or more of these categories.
A long time ago I used to participate in the rec.games.frp.advocacy group on Usenet, and one of the things that discussion circled endlessly around–to the point of diminishing returns, and eventually nauseam–was theories of what roleplaying games were about, and in particular one theory called The Threefold Model. (The Threefold Model basically pictured rpgs or sometimes players as occupying a triangle, where the vertices were Drama, Game, and Simulation, and that’s about all I’ll say about that for now.) In the end R.g.f.a became several long flamewars, thus fulfilling its original purpose (in the Usenet hierarchies .advocacy groups were where they tried to shunt neverending flamewars like Mac vs. PC so the main groups had a better signal to noise ratio), but leaving people who wanted to talk seriously about RPGs in more abstract terms without a real place to do it. As Usenet sank and the Web rose, several forums attempted to fill this need, at least for certain subsections of the audience, one of the most notorious being The Forge. (Notorious because of the prickly personality and heavy hand of its owner and chief moderator, Ron Edwards, and a cliquishness that really rubbed a lot of people the wrong way.) GNS was the name of Ron Edwards’ own theory, about which the less said the better, but at least it inspired the model in Jeff’s Gameblog that I linked to above.