645 Athletes
590 US athletes will be at the Beijing Olympics.
With 639 athletes, China has the most athletes in the Beijing Olympics. The country that has the most athletes that traveled to China to the Olympics would be the the US with 595 athletes.
The US has 529 athletes in the 2012 Olympics.
The United States will have 647 athletes at the 2008 Games in Beijing.
530 US athletes will be participating at the 2012 London Olympics.
Vancouver
596
According to the on-screen information during the opening ceremonies/parade of nations, there are 647 US athletes in Beijing.
539
530.
None but me