Reuters: A climate deal among world leaders including U.S. President Barack Obama puts off many tough decisions until 2010 and sets the planet on track to overshoot goals for limiting global warming. Obama spoke of "the beginning of a new era of international action" but many other leaders said it was "imperfect", "not sufficient" and at best a "modest success" if it gets formally adopted by all 193 nations in Copenhagen on Saturday. Problems faced by China and the United States — the …