Stepping up its competition with Nielsen, the dominant provider of audience measurement services to broadcasters and advertisers, Rentrak announced today (Monday) that is had reached an agreement with DISH network -- a deal that gave Rentrak the ability to boast that it now provides "the largest national TV viewing data set," covering 210 TV markets with more than 15 million TV sets. In a statement, Bill Livek, CEO of Rentrak, said that the company would now be able to offer a "massive national data set comprised of anonymous, second-by-second viewing information (including live and time-shifted DVR click-stream viewing)."