Revenge of the Swifties, courtesy of a potential antitrust lawsuit. Shares of Ticketmaster parent company Live Nation Entertainment (LYV 0.06%) plunged this week, falling 11.2% through Friday trading at noon ET, according to data from S&P Global Market Intelligence. Live Nation merged with Ticketmaster in 2010, creating a dominant ticketing company for the highest-profile concerts. However, this week The Wall Street Journal reported the Department of Justice is preparing to sue Live Nation for alleged antit ...