Wired has the story about an upcoming conference devoted to viral marketing. Organizers have "three goals in mind: to propagate ethical guidelines for word-of-mouth marketers, to establish industry measurements and to teach best practices so marketers can learn how to do it."
The most famous case of viral marketing is Burger King's Subservient Chicken. Recently ADWEEK, in a great case study, asked: "aside from Web traffic, did the campaign actually drive customers into stores to buy the sandwich?....the company has seen 'double-digit' growth of awareness of the TenderCrisp Chicken Sandwich and 'significantly increased' chicken sandwich sales." So the client seems pleased. The site is still up and still fun. The lone dissenting voice is, as can be expected, that of a franchisee: '"I'm more of a traditionalist. I like to see the food.'" That guy -- what a buzz kill.
UPDATE: Steeplechaser has more.