Balter's company, BzzAgent, has grown exponentially in just a few years; it now coordinates an army of 75,000 volunteers who talk up products they genuinely love. The big lesson from BzzAgent's success is that companies don't need to win over experts to drive word of mouth, they just need to reach ordinary consumers. Grapevine teaches the skills BzzAgent has perfected to make them a leader in their field. The book also features many BzzAgent campaigns...