Social is all about spreading. But before you try to say the word v...v...vi...viral (had trouble spitting that one out), there is a key difference that Jenkins pointed out between viral and social spreading. People spread viruses by accident. It is not intentional to give someone a cold -- at least I sure hope not -- but when people pass things to each other by way of social interaction, there most certainly is intent. This means that people are rational about spreading something through their social connections.
To ask for something to spread virally, shouldn't really be viewed as "tricking" people into spreading something for you. I know from speaking to marketers that they don't want to "trick" people, so what they need to do is to start evaluating why people would want to "spread" their brand -- NOT thinking about how to make something so funny or edgy that people will spread their brand by accident. People are not stupid. They know when a brand marketer creates a widget, the marketer is in effect asking people to spread the brand for them. The biggest problem marketers have is fooling themselves into thinking that in the absence of benefit, people are going to want to help spread their branded widget. Too many times this is just not the case.
It's interesting to look at how polar opposite the problems of entertainment and marketing are. For most large entertainment companies, the discussion is still on how to prevent people from spreading content without permission -- whereas marketers are looking for ways to get people to spread their content as much as possible. I am sorry, but if you think about it, it is a little funny. It is especially funny when you think about how natural it is that one should solve the other's problem, but we all know it's easier said than done.
On another note, if you want a really interesting perspective on how marketers are voting with their wallets on professional entertainment distributed through the Web vs. amateur entertainment, check out Scott Karp's article, "Hulu to Match YouTube's Revenue: Ten Observations For The Future of Media," which does an amazing job of highlighting 10 insights we should take from how the two companies are performing. The piece points out that professional, legally distributed content still has significantly more value than amateur content. The question we should be asking ourselves is, why this is the case. Is it that the opportunity for a brand to reach a person is more or less valuable depending on the quality of the content? It seems that the situation is more a product of brands lacking a scalable way to achieve reach in a truly appropriate context in the more fragmented media of YouTube, so they settle for greater reach in an acceptably appropriate context on Hulu. It is a mouthful, but consider the issue. I think you'll agree -- or perhaps not. Let me know.