Brevity may be the soul of wit, but what does wit matter if no one's listening? On Twitter the potential exists for many people to listen even if they aren't connected. The reach of Twitter creates the possibility of a shared experience that extends well beyond the immediate network of a user:

When the Japanese anime movie Laputa: Castle in the Sky was televised in 2011, viewers joined forces to support the movie's characters and symbolically help them cast a spell by Tweeting at the same time. At the peak of this unified movement, they were sending 25,088 Tweets per second (TPS).

Following the end of the Euro 2012 Finals, 15,358 TPS were sent as fans shared their joy or frustration over the outcome.

Similarly, when the New York Giants took the lead with int he game with 57 seconds to spare, spectators turned to Twitter at a rate of 10,245 TPS.

Beyonce's pregnancy news garnered 8,869 TPS as excited fans spread the word.

These people were united by an event that they otherwise would have experienced in a much smaller capacity, particularly when you consider that they didn't have to be a fan or otherwise actively watching the event in question. Simply being exposed to a Tweet added them to the experience.

In a similar example, when the Discovery Channel aired a mockumentary raising the possibility that mermaids could be real, marine biologists on Twitter were quick to cry foul. Southern Fried Science blogger David Shiffman's prolific Tweets on the subject caught the attention of Slate, Grist, and The Lead. While these listeners amplified David's message beyond the social network, within the network Retweets, shares, and hashtags also expanded the experience of science and learning and disbelief beyond David's immediate radius. These actions allowed other users to experience the mermaid mockumentary and become a part of the conversation even if they themselves had not seen the show.

This is the power of Twitter: it's live, it's public, and it's designed to encourage commentary. And with 200 million users, the discussion can invite diverse voices resulting in uncommonly powerful shared experiences. Why is this important? Because when properly amplified, these voices can be characterized as a mob.

We saw this happen just recently here on the Scientific American blog network. In a case that received widespread attention, Dr. Danielle Lee's post regarding her being treated most disrespectfully by another outlet was initially removed by Scientific American for what were ultimately revealed to be legal reasons. It was restored once the corporation had verified the reported exchange. However, in the time it took for that to happen, the outcry on Twitter was so immense as to attract Slate, ABC News, Huffington Post, and Jezebel to name but a few outlets. People reacted viscerally to Danielle's treatment and added their own experiences of sexism and unprofessionalism to her own to amplify the reach of this initial event. They called for immediate action—for an apology from Scientific American and for the removal of the offending party—and declared their solidarity with Danielle. However, the processes within Scientific American were not poised for such immediate action, which led to calls to boycott the outlet as reactions seemed to go unanswered and—worse—unacknowledged.

Was this a mob? Some said yes, and called for moderation. As far as I can tell that seems to be the extent of the call to action—boycott or wait. This is notable because there are cases where Twitter mobs call for violence, including rape. As far as I know, no one suggested violence. But does then the absence of violence mean that this was not a mob? Mobs are angry, mobs want action but do they have to be violent?

Based on a recent report from Forrester, this type of online response is indicative of the "mobile mind shift." That is, the prevalence of mobile technology has produced a sense of connectivity that expects a response to the person's immediate need. Social networks deliver exactly this: We share instantaneously whatever we're experiencing and invite others to respond. People placate, people congratulate, people commiserate, and people can try to regulate wrongs. In this case, a need was expressed and when that need wasn't met, it prompted other people to respond. They added their voices to magnify the need. While we're all probably guilty of reaching for Google to answer a question for which the answer just escapes us or have hit Retweet on an article we perhaps haven't read, the mobile mind shift doesn't quite capture the complex emotions that help sustain a group-shared experience on a social medium. While it identifies the impulse to respond and share, it doesn't address the drive to do those things.

Twitter is a media rich property. It allows users to share a lot of information and share that information quickly. In social interactions, people want to control the impression that others may ultimately form of them. In this regard, what we choose to share and comment on generates an image of both ourselves and the larger community we belong to. We define our authenticity by answering both "What do we stand for?" and "How will we fight for it?" when we join a Twitter mob. We become active in the experience and self identify as custodians for our communities. Hashtags then become markers of solidarity. What's remarkable is the ways in which experiences can overlap and different groups can find strength and support through hashtags as is evident from #ripplesofdoubt, which has expanded to include stories of harassment from all corners of professionalism.

Sometimes public outcry results in change, sometimes it doesn't. In a medium where brevity deploys snark and wit with equal measure, the noise generated can quickly gain momentum and take on a life of its own. And perhaps that is the mob—not so much the people, but the momentum itself. Maybe it's not the number of people, or the volume of their cries, but it's the the outcome of that momentum that distinguishes a mob from a mob.