Bernard Poussot has been appointed president and chief executive officer, Wyeth, effective January 1, 2008. He replaces Robert Essner, who will continue as chairman of the board of directors for the transition period. Mr. Poussot joined the company in 1986 and was appointed president of Wyeth-Ayerst International in 1996. He was promoted to president of the worldwide pharmaceutical business in 1997 and in 2002 he was promoted to executive vice president, Wyeth, responsible for Wyeth R&amp...