I think too many marketers look at social influence as if it's some kind of new phenomena. I don't believe it is. In the early days of television, we used the newscaster or the actor to pitch items to the audience. The three networks owned the audience and there was trust and authority established… so the commercial advertising industry was born.
While social media provides a two-way means of communication, social media influencers are still often one-way influencers. They have the audience, though much smaller and niche to the industry or the topic at hand. For marketers, the problem is the same though. The marketer wishes to reach a market and the influencer influences and owns that market. So just as companies purchased advertisers and had spokespeople pitching them, we can do the same with social influencers.
This infographic from MBA in Marketing speaks to how one can find and utilize social influencers. I'm not sure I agree with the term Mega Influencers within the infographic, though. I'd, instead, call those social media social influencers. There are still specific topics I trust those authorities on… but not all. I'm going to trust Gary Vaynerchuk on wine and entrpreneurship, Scott on cars, and Mari on Facebook Marketing… but I'm not going to trust them to arrange my stock portfolio!