Penenberg, Adam L. Viral Loop: the power of pass-it-on

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They call it web 2.0, this latest incarnation of the World Wide Web. A significant proportion of online content now comes from everyday users. Much of this is via social media networks. You know the big ones: Facebook, MySpace, YouTube, and LinkedIn. Dozens of also-rans abound, some with similar annoying interCapitals: TravBuddy, DeviantArt, or Care2, anyone?

Online social networks are responsible for a steeply increasing proportion of Internet use. Their growth depends on users passing on information about the websites, which in turn engenders more users. If, on average, each user begets at least one other user, the number of users will increase exponentially. This is the viral loop.

Viral loop tidily presents a history of viral case studies from analog to digital. Penenberg begins in the real world, with Tupperware, and ends with viral applications that piggyback on top of existing websites, such as PayPal (eBay), YouTube (MySpace), and widget-application rivals RockYou and Slide (Facebook). Off-the-chart growth of diverse sites (such as the website of questionable taste, Hot or Not, or photo-sharer Flickr) often led to huge dollar amounts when their creators sold up. Barack Obama’s team imprinted a viral loop in his political campaign, with great success. It included social networks, mobile Internet, and the online community of

This history of social networking benefits from in-depth first-person research.

Viral Loop suggests a company eschew any marketing expenditure, as these successes depend on ‘organic’ growth models. Interestingly, no mention is made of Wikipedia, which surely owes some of its success to viral means. Penenberg also seems less comfortable discussing Twitter, which is surprising considering Twitter’s high rate of click-through to links mentioned in users’ “tweets” – surely an achievement by viral standards.