This article on Viral Videos includes an instructive perspective from Yahoo Lab’s Duncan Watts on the "Big Seed" Viral Marketing Strategy:

“Genuinely independent viral success has always been a lucky exception. ­Duncan Watts, a pioneer in the network science that helps us understand internet behaviour, says the most effective way to go viral in a big way is to do it in many small ways – a "big seed" strategy where you push your content out to a lot of different places to raise your chances of several unrelated people passing it on. If you think this is the kind of thing a wealthy major label will be able to do a lot more effectively than an individual, you'd be absolutely right. The big seed theory doesn't see the internet as big media's graveyard, more its allotment.”

http://www.guardian.co.uk/music/2010/feb/04/viral-video-ok-go

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