I am once again dipping my toe in the Twitter waters (horrid mixed metaphor—for more of the same, follow me at twitter.com/ahc). It seems to me that Twitter serves distinct functions for two different groups of people. For some, who keep their connections under the magic 150 number identified by Robin Dunbar, it is indeed a social network. But for others it's media, in the literal sense: a tool that stands (i.e., mediates) between people, making communication possible to a larger number than one could ever address in person. It may well be that many of the most powerful media of the next generation will have this hybrid quality—keeping us connected, in some thin but real sense, to our "real" friends, but also allowing us access to the thoughts of folks like Barack Obama. And the second group, the "broadcasters," will likely be the drivers of whatever business model eventually makes these networks sustainable.

re: 3 12 120, communication, community, technology and change, trends, twitter

Andy:

Robert Metcalfe, co-inventor of the Ethernet, noticed that communication networks tend to increase exponentially with each single addition, a logic that today is called Metcalfe’s Law. Think of a fax machine sitting alone and unplugged in your office; it has little value by itself. But plug it into a network of fax machines around the world, and suddenly that communications tool has huge potential. . . .

But Metcalfe’s concept doesn’t apply to Twitter. The explanation why comes from two fellows named Zipf and Dunbar. Back in 1935, linguist George Zipf noticed that words in the English language are used in an interesting pattern. “The” is spoken most commonly, making up 7% of all utterances; “of” is the second-most common word, used exactly one-half as often as “the”…and the pattern continues with the 100th word in popularity being used only 1/100th as often. Zipf’s Law suggests that each subsequent thing in any series (such as your Twitter contacts) has predictable diminishing value. Your spouse is more important than your best friend, who outranks your boss, colleague, and that guy you met on a plane from Chicago. Inside the 2.3 million-strong Twitter network, not all connections are equal, and some will never be used at all. You will probably never send tweets to ice skaters in Finland.

Further depressing Twitter’s internal value is a concept from British anthropologist Robin Dunbar, who noted in 1992 that humans—like other primates—can handle only 150 relationships. If we try to add many more connections, our little brains get overloaded.

These are just theories, but they point out that Twitter is not a vast communications network of 2.3 million users squared. Rather, it consists of small pools of people with gaps and limits on how they interact. This is important to marketers and investors, because it puts big brakes on how internal communications could propagate inside any social media network.