Money has historically been the most commonly understood (and easily measurable) metric of power. In recent decades knowledge has also become an accepted benchmark of influence. In our open, modern society, reputation may be one of the single biggest sources of power a person can have.
By studying click-through rates--the amount of clicks a tweeted link receives--Zarrella was able to graph celebs' influence on their followers (see chart below). Some of the names are not so surprising (Ashton Kutcher), but others, including British actor Stephen Fry and poet laureate "Weird Al" Yankovic, may come as more of a shock.