Social influence in the physical world can be correlated with intangible attributes like charisma, attraction, and charm. In translation to a digital context, the concept of influence is still very much connected to these types of human elements, but their impact becomes measurable. The value in determining how much impact an individual has on a specific topic of interest is becoming clearer as more companies depend on digital communities for product awareness. Using a defined metric for domain-specific impact factor in conjunction with predictive modelling, we are able to visualize some interesting trends of influence among Twitter users. Not only can these findings assist in integrating social media into an effective marketing model, they can potentially outline a more direct return on investment.