The 2009 World Junior Chess Championships, taking place in Argentina, have completed seven rounds. The only U.S. players, GM-elect Alex Lenderman and GM-elect Ray Robson, both drew their 6th-round games and won their 7th-round games. They have therefore moved up a bit in the standings.
In sole first place with 6.0 points is GM Sergei Zhigalko of Belarus. Lenderman stands a point behind, in a 7-way tie for 5th-11th place. A half-point behind Lenderman is Robson, tied with 10 other players for 12th-22nd place. In total, 84 players are in the men's under-20 championship. There are no U.S. players in the 45-player women's under-20 championship.
You can monitor the tournament's results at this English-language site.