The most potentially transformative impact of social media is its ability to encourage brands to marry profit and purpose. The reason brands participate is that such outreach earns those companies social currency enabling them to start or participate in conversations that connect them to consumers in meaningful ways.

The theory of social contracts extends as far back as Plato. However, it was the great 18th century social philosophers John Locke, Thomas Hobbes, and Jean-Jacques Rousseau who brought the concept of a social contract between citizens and governments sharply into political thinking, paving the way for popular democracy and constitutional republicanism.

The advent of Google+ and the emergence of the personalized web means this is more true than ever. Brands, and their advertising partners, must wake up to this challenge and define themselves with clarity, consistency and authenticity. Otherwise they just might find themselves shouting in a ghost town.

A world in which government is burdened by historic debt, philanthropy has limited resources, and the private sector is only interested in its own personal gain is simply unsustainable.

Today's consumers are eager to become loyal fans of companies that respect purposeful capitalism. They are not opposed to companies making a profit; indeed, they may even be investors in these companies - but at the core, they want more empathic, enlightened corporations that seek a balance between profit and purpose.

Since most corporate competitors have the same problems with sustainability and social reputation, it's worth trying to solve them together.

In fact, I believe the first companies that make an effort to develop an authentic, transparent, and meaningful social contract with their fans and customers will turn out to be the ones that are the most successful in the future. While brands that refuse to make the effort will lose stature and customer loyalty.