DigitalSeparated at Birth: CNN’s Carol Costello and…By Betsy Rothstein|May 20, 2011 ShareBy Betsy Rothstein|May 20, 2011 ShareToday’s twins have driven a D.C. media type away from CNN this morning. “I have to change the channel.” he wrote into FishbowlDC. “Ahhhhhhh!”The pairing is CNN contributor to “American Morning” Carol Costello and Aerosmith’s lead singer Steven Tyler. Adweek Adweek