Games with explicit hierarchical systems are rare, but the concept is particularly well suited to a social graph environment. As one example, in the play-by-mail game Renaissance, a new player begins with few resources, and can progress much more quickly in the game if he swears allegiance to a more powerful liegelord, or joins an existing trading house as a subordinate. In Slobbovia, a Diplomacy variant, players who control more than a few provinces are required to turn control of some over to a subcommander -- who can declare independence if not satisfied with his commander's play.
Hierarchies are useful in acculturating newbies, in fostering continued communication up and down the hierarchy, and in fostering team play, but with the additional advantage that 'teams' can be more fluid than in games with explicit teams, since players may change hierarchies, and move up or down within their existing hierarchy.
In a non-digital role playing game, much of the pleasure of play derives from playing a role: from making decisions in the spirit of your character, from a vicarious experience of what it is like to be a person living in an imaginary universe, from speaking and acting "in character."
In some types of role playing games -- in LARPs, in many indie "narrativist" RPGs, in story games, and in jeepforms -- the line between 'game' and 'theater' is blurred to the point that the distinction between between "role playing" and "acting" is moot.
Role playing, in this case, is not merely about vicarious experience, however; it's also about showing off for, and entertaining your friends. Saying interesting things, acting in unpredictable (but character-consistent) ways, and improvising with your friends becomes critical.
Performative play like this need not be as freeform as in tabletop RPGs, however; as an example, one of the most popular games on the old Sierra Network (a pre-Internet commercial online service) was called Acrophobia.
The game is very simple; a group of players are served a random string of characters. Each must devise a sentence in which the first characters of the words of the sentence together produce the random string they were served.
When all players have entered a sentence, they are revealed, and the players then vote on which they like best; after several rounds, the player with the most cumulative votes is the winner.
In this case, the way to win is to come up with the sentences your fellow players will think are wittiest and most amusing; despite the restrictive, formalist nature of the game, it is performative at its essence.
Performative play is utterly social in nature, and possible only in multiplayer games; it is also something to which online games have always been well suited. The existence of a social graph, making it easier to play with actual friends instead of strangers, should foster performative play more effectively than other online environments. And yet not only do social games not foster performance of any kind, they eschew the kinds of communication -- messages (other than the preformatted) and chat -- that could support performance.
In recent months, the number of monthly active users for social games has dropped a bit, and there's been some discussion of the idea that the social game boom may have passed its peak. No good thing lasts forever, and unquestionably the success of social games owes some debt to their novelty, and novelty wears off quickly. In my opinion, this is a temporary matter, largely resulting from the sameness of available games; one new game exploiting a play pattern social gamers haven't seen before will be sufficient to restore interest in the field.
Where that play pattern will come from is a matter of conjecture, but to my mine one place to look is obvious: in fostering gameplay that is itself social, in a meaningful sense.
As social media natives, social games need to become truly social. This means more than exploiting the social graph for business model purposes; it means figuring out how to use the social graph to provide unique and compelling gameplay.
Social games must become actually social.