This Gawker item about the Facebook redesign offers a useful phrase for thinking about Twitterification generally: We are expected to be, or become, "omnivorous consumers of momentary trivia." Not only that, but we are expected to produce that trivia ceaselessly and eagerly. This calls to mind Foucault's ideas about power exercising itself not as repression -- that is, as forbidding us to speak or to act in certain ways -- but as permission, as a kind of broad encouragement to speak (albeit through discourses that constitute our identities along certain prescribed lines). Our participation lets power work through us, which we can experience as being exciting -- as being part of the action; we are all under surveillance, but we understand that emotionally as "Hey, we're all celebrities!" Foucault calls it "control by stimulation." This is why people seem to feel compelled to use Twitter. We want to participate, want to be counted, want to count.
I assume someone out there is working on a dissertation (or has at least posted a really incisive blog entry -- maybe among these) that does a Foucaldian analysis of social media (which I would be eager to read actually) -- it fits so well with his predictions of a panoptic society. We are spying on each other (that's certainly how it feels when someone tags me in a high school photo), and confessing ourselves to everybody else (in hourly 140-character broadcasts), and mistaking it all for entertainment consumption, ordinary leisure activities.
Social media tends to be understood as a kind of freedom to express ourselves in a new way; interactivity liberates us from one-way communication and affords us the opportunity to speak and participate. But this "freedom" can function as a kind of compulsion, as part of what Baudrillard et al. called the "fun morality." Foucault insisted that power is both decentralized (not a matter of some authority telling you what you must do) and productive (it allows more things to have a kind of social being, not fewer; creates more data, not less). In an interview in Power/Knowledge, he says, "What makes power hold good, what makes it accepted, is simply the fact that it doesn't only weigh on us as a force that says no, but that it traverses and produces things, it induces pleasure, forms knowledge, produces discourse." Various modern technologies have brought about what he calls "a new economy of power" that allows "the effects of power to circulate in a manner at once continuous, uninterrupted, adapted, and 'individualized' throughout the entire social body." In other words, there is no way to sneak around power because we are basically bathing in it, breathing it in and out at all times. Twitter-style discourse is the latest instance of a social discourse that functions this way, reinforcing the compulsion to confess. The "effects of power" Foucault is talking about, I think, is a matter of our being available -- power makes us available to various social institutions so that are efforts can be harvested and our behavior channeled accordingly without our even conceiving of resistance.