Which CEO has the most influence when it comes to social media?

Warren Buffett? Nope. Michael Dell? Not a bad guess, I suppose. Twitter’s Dick Costolo? He’s up there. AOL’s Steve Case? Good try. Richard Branson? You’re getting warmer.

Facebook’s Mark Zuckerberg? According to this study, he doesn’t even make the top fifty.

Yes indeed. According to the Reuters & Klout 50, which measures the most influential executives online, it’s Oprah Winfrey who ranks as the most influential social CEO, ahead of Rupert Murdoch, Richard Branson, Mark Cuban and Tim O’Reilly. Twitter co-founder (and now Square CEO) Jack Dorsey placed in fifth, while Twitter CEO Dick Costolo was fourteenth.

Check out the incredibly well-designed infographic below for your top forty.

Note: As beautiful as it is, this visual uses data from November 29, 2012. While the top five spots remain the same, there’s been some movement in the chart since then.

(Source: TopManagementDegrees.com.)