The BIG development is an unscheduled and unannounced in advance three-day visit by Treasury Secretary Geithner to China on Sunday, May 31. Mr Geithner will meet with all the top Chinese officials including President Hu Jintao and Premier Wen Jiabao. He has no other Asian stops on his itinerary. This surprise visit has the flavour of a "summons". The participants certainly have a lot to talk about.