People do not choose RPGs based on their narrative needs or story needs. Most people do not really have any of those kinds of needs; they haven't thought about them, wouldn't feel strongly about them even if they did think about them, and would probably just make shit up if asked about it from fear of not looking intellectual enough.
Most people would also not have a clue which games would fit which "playstyles", given that no one can seem to agree on how to categorize playstyles in the first place.
Instead, people will usually gravitate to differing RPGs for entirely shallow reasons, purely aesthetic elements that reflect more about their extrovert personality than their introverted "needs". You can identify types of gamers and the kind of games they enjoy more from the kind of dice that they favour than from any subjective set of jargon about "playstyles".
Gamers that like D20s are mostly interested in rapid, fun play. They like a good solid ruleset, want games to be coherent without being too completist, and will in no way be picky or selective about the games they play as long as its fun to play. They are by a VAST majority the most common kind of gamer.
Gamers that like D6s don't care about how a game looks, they care about how it works. What kind of dice a game use doesn't matter, a simple D6 is enough, its more important that the rules BE there. They are technical perfectionists, wanting games that function with detail and consistency. They don't fear big rulebooks. They want games that demand a serious level of commitment; and are seeking out a kind of perfect game system, a set of rules so thorough and complete that they cover everything.
Gamers that like percentile dice (not D10s, but rolling 2D10s as percentiles) are a cross between D20 and D6 people. They want something solid and dependable, but simple to understand. So simple you can express it in percentiles. Getting to the game is very importance, but the mechanics have to be there.
Gamers that like D10s, on the other hand, prefer play that's mostly style over substance. D10s are the only dice that aren't Platonic Solids. This clearly means that D10 lovers are obviously degenerates (unless they're percentage lovers, who aren't really dice lovers at all). They actually care more about a game looking and acting cool and being thought of as "hip" than actually working. Ease of play and fun aren't as important as the "fulfillment" of seeming to do something important.
Gamers that like D12s or D8s are the ones who enjoy weird for weird's sake. They aren't as purely solipsistic as the D10-lovers, they enjoy mechanics, but they want mechanics that aren't orthodox. They want mechanics that are generally counter-intuitive; and generally don't want complexity as much as they want originality. They aren't looking for the perfect game system, they're looking for a new game system every week.
Gamers who like D4s are sadomasochistic sexual deviants who enjoy being molested by lizards.
(originally posted April 24, 2006)