Believers in the potential of Web 2.0, such as we at Vukutu, think it will change many things — our personal interactions, our way of being in the world, our social lives, our economic lives, even our sciences and technologies.   The basis of this belief is partly by comparison with what happened the first time social networking became fashionable in western society.   This occurred with the rise of the Coffee House in western Europe from the middle of the 17th century.
Coffee, first cultivated and drunk in the areas near the Red Sea, spread through the Ottoman empire during the 16th century.   In Western Europe, it became popular from the early 17th century, initially in Venice, becoming known to educated Europeans roughly simultaneously with marijuana and opium.  (An interesting question for marketers is why coffee became a popular consumer product in Europe and the others did not.)  Because of the presence there of scholars of the orient and scientists with an experimentalist ethos, coffee first arrived in the British Isles in Oxford, where it was consumed privately from at least 1637;  the first public coffee house in the British Isles opened in Oxford in 1650, called the Angel and operated by a Mr Jacob.  The first London coffeehouse was opened in 1652 by Pasqua Rosee; the same mid-century period saw the rise of public coffee houses in the cities of France and the Netherlands.  For non-marketers reading this, it is worth realizing that opening a coffee house meant first having access to a regular source of coffee beans, no mean feat when the only beans then grew in the Yemen and north-east Africa.

Facing competition, coffee houses soon segmented their market, and specialised in particular activities, types of conversation, or political positions (sound familiar,  bloggers?), and provided services such libraries, reading rooms, public lectures, scientific demonstrations and auctions. Educated people and businessmen would often visit several coffee houses each day on their rounds, to collect and trade information, to meet friends and colleagues, to commune with the like-minded, and to transact business.  The coffee houses were centres for learning and debate, just as blogs are today, as well as places of economic exchange.
What were the consequences of this new mode of human interaction?  Well, coffee houses enabled the launch of at least three new industries — insurance, fine-art auctions, and newspapers — and were the physical basis for modern stock exchanges.  For instance, English insurer Lloyds of London began in Edward Lloyd’s coffee house in 1688.  And these industries themselves enabled or facilitated others.  The development of an insurance industry, for example, both supported and grew alongside the trans-continental exploration undertaken by Dutch, English and Iberian merchant shipping fleets:  deciding whether to invest in  perilous oceanic voyages required some rigour in assessing likely costs and benefits if one wished to make a long-term living from it, and being able to partition, bundle, re-bundle and on-sell risks to others.
And coffee-houses even supported the development of a new science.  In the decade around 1665, the modern idea of mathematical probability arose, seemingly independently across western Europe, in what is now Britain, France, Italy, the Netherlands and Switzerland.   There is still some mystery as to why the mathematical representation of uncertainty became of interest to so many different people at around the same time, especially since their particular domains of application were diverse (shipping accidents, actuarial events, medical diagnosis, legal decisions, gambling games).  I wonder if sporadic outbreaks of the plague across Europe provoked a turn to randomness.  But there is no mystery as to where the topic of probability was discussed and how the ideas spread between different groups so quickly: coffee houses, and the inter-city and inter-national information networks they supported, were the medium.
What then will be the new industries and new sciences enabled by Web 2.0?
POSTSCRIPT: Several quotes from Cowan, for interest:

“No coffeehouse worth its name could refuse to supply its customers with a selection of newspapers.  . .  . The growing diversity of the press in the late seventeenth and early eighteenth centuries meant that there was great pressure for a coffeehouse to take in a number of journals.  Indeed, many felt the need to accept nearly anything Grub Street could put to press.  . . . Not all coffeehouses could afford to take in every paper published, of course, but many also supplied their customers with news published abroad.  Papers from Paris, Amsterdam, Leiden, Rotterdam, and Harlem were commonly delivered to many coffeehouses in early eighteenth-century London.  The Scotch Coffeehouse in Bartholomew Lane boasted regular updates from Flanders on the course of the war in the 1690s.   Along with newspapers, coffeehouses regularly purchased pamphlets and cheap prints for the use of their customers.” (pp. 173-174).

“Different coffeehouses also arose to cater to the socialization and business needs of various professional and economic groups in the metropolis. [London]  By the early decades of the eighteenth century, a number of separated coffeehouses around the Exchange had taken to catering to the business needs of merchants specializing in distinct trades, such as the New England, the Virginia, the Carolina, the Jamaica, and the East India coffeehouses.  Child’s Coffeehouse, located conveniently near the College of Physicians, was much favoured by physicians and clergymen.  Because such affiliations were well known, entry into one of these specialized coffeehouses offered an introduction into the professional society found therein.” (pp. 169-170).

“The numerous coffeehouses of the metropolis were greater than the sum of their parts; they formed an interactive system in which information was socialized and made sense of by the various constituencies of the city.   Although a rudimentary form of this sort of communication circuit existed in early modern England (and especially London) well before coffeehouses were introduced in places such as St. Paul’s walk or the booksellers’ shops of St. Paul’s churchyard, the new coffeehouses quickly established themselves at the heart of the metropolitan circuitry by merging news reading, text circulation, and oral communication all into one institution.  The coffeehouse was first and foremost the product of an increasingly complex urban and commercial society that required a means by which the flow of information might be properly channeled.” (p. 171)

 
References and Acknowledgments:
My thanks to Fernando E. Vega of the USDA for pointing me to the book by Cowan.
Brian Cowan [2005]:  The Social Life of Coffee:  The Emergence of the British Coffeehouse.  New Haven, CT, USA:  Yale University Press.
Ian Hacking [1975]:  The Emergence of Probability: a Philosophical Study of Early Ideas about Probability, Induction and Statistical Inference. London, UK: Cambridge University Press.
Fernando E. Vega [2008]: The rise of coffee.  American Scientist, 96 (2): 138-145, March-April 2008.