Good point about how people think about social. They say, "hey let's create a viral campaign," and dump all this money to agencies to create them. When campaigns fail, they say social doesn't work. What they don't get is exactly that, social is an on-going series of experiments, you're basically trying to create something that will get carried on and shared by a number of individual human being. Optimizing to Google's search algorithm is a relatively simple task compared to optimizing your message to one that resonates with hundreds and thousands of human beings.