Leighton Meester poses for InStyle Magazine, March 2009 issue.Leighton Marissa Claire Meester is an American actress and aspiring singer-songwriter, best known for her role as Blair Waldorf in the TV show Gossip Girl. Leighton Meester is also cover girl of Seventeen Magazine in March 2009. Leighton Marissa Claire Meester is an American actress and aspiring singer-songwriter, best known for her role as Blair Waldorf in the TV show Gossip Girl. Her first acting role on a television program was on NBC's legal drama Law & Order in 1999.
