Prodigy Communications Corp, the White Plains, New York-based ISP and telecommunications company, has appointed David Trachtenberg as its new president and chief operating officer. Samer Salameh remains as chairman and chief executive. Prodigy, one of the oldest online service providers, filed for its IPO in September, hoping to raise up to $86m (09/28/98). Trachtenberg was formerly executive director of online marketing at MCI WorldCom Inc where he was in charge of MCI’s residential and small business internet operations. Before that he headed brand marketing at MCI and was responsible for the marketing of the company’s MCI One domestic, long distance calling card and other services.