Too bad. Since its founding, this organization has consistently supported Communism and Communist revolutions. The Catholic Church is not a member and should not have anything to do with the WCC. The goal of the WCC is to unite all Christian organizations into a new World Church.
Catholic Culture: Pope Francis will visit the Swiss city on June 21. Over 300 Protestant and Orthodox communities belong to the ecumenical body, founded in 1948. See here. And National Catholic Register article here.