For all the objections raised over the role of Sharpton at MSNBC, though, there's no escaping his impact on television where it counts: in the ratings. In the world of cable television, which monitors progress according to the ever-changing metrics of viewers and households, Sharpton has played a part in MSNBC's continued strength in prime-time viewership, helping the network beat CNN in prime-time cable viewers for the third straight year.

Sharpton is helping to solidify an audience of black viewers that was well-established before he arrived; MSNBC has been a consistent magnet for African-American viewers, boasting its place as No. 1 among black viewers in prime time for 22 straight months.

In a Dec. 19 press release, the network reported that "since PoliticsNation debuted in the time period, MSNBC is topping CNN by 17 percent" in the key demographic of viewers between 25 and 54. "MSNBC topped CNN in every hour from 5 p.m.-10 p.m. ET for the year," the network reported.

PoliticsNation tops CNN's John King USA by 50 percent among total viewers (767,000 versus 512,000), according to TV Newser.

Sharpton's presence may yield more dividends. Recent MSNBC viewers, for example, have no doubt noticed a new promotional spot in which his face is positioned next to those of network heavy hitters Ed Schultz, Chris Matthews, Rachel Maddow and Lawrence O'Donnell. The ad, part of MSNBC's "The Place for Politics" campaign, suggests that Sharpton will be a full partner in the network's upcoming coverage of the 2012 presidential election.

And there's talk that Michael Eric Dyson, the author and Georgetown University professor who has also been a substitute host on MSNBC, could be next to join the network, in a role not unlike Sharpton's own.

In an interview with the Daily Beast, Dyson offered what may be an object lesson in how the process of reporting the news may have been transformed -- and how the rules of the game have changed, along with the players.

"With the evolution of social media that includes blogging, Facebook and Twitter, who and how information is delivered has changed tremendously," Dyson said. "The landscape for news is a different place, and people have to accept that."

Michael E. Ross is a regular contributor to The Root and the author of American Bandwidth, on the Obama campaign and presidency. He blogs on politics and national affairs at Short Sharp Shock.

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