Word-of-mouth has always been a great way for Rainmakers to move the needle, but digital and social media has made sharing knowledge and opinions more prevalent and powerful, making it essential for brands to understand how to harness its influence. In every product category, there are consumers who become Category Influentials. These are the people who GfK Roper defines as highly trusted, well-informed consumers who make frequent recommendations across broad social networks. And the most significant group of social influencers are not who you might think.