By Justin Bachman, Bloomberg As everyone learned when a passenger was forcibly removed from a United Express flight, social media and the ubiquity of mobile phone cameras have shifted the ground rules for airline customer service. The best and worst corporate interactions speed across the Internet, with potentially dire results for corporate targets of public anger. For air carriers in particular, “the world changed” last April after the Chicago dragging incident, Oscar Munoz , chief executive of United Continental Holdings Inc., said in a June talk at the Wings Club in Manhattan.