&$ &$China's famous basketball star Yao Ming (C front), who is also the ambassador for the 2010 Shanghai World Expo, speaks at a mobilization meeting for the Shanghai Expo in Shanghai, east China, Jan. 21, 2010. Shanghai Expo entered its 100-day countdown on Jan. 21. (Xinhua/Pang Xinglei)&$ &$ More than 50 incumbent heads of state or government have expressed intention of visiting Shanghai to ...