United Airlines has been given the go ahead by the US Dept of Transportation to commence new direct flight services between China and the United States.  United Airlines will become the first US carrier to offer a new daily nonstop service between San Francisco and Guangzhou.  The carrier already flies nonstop to Beijing from San Francisco, Chicago and Washington D.C. and nonstop to Shanghai from Chicago and San Francisco.  Meanwhile Delta Air Lines has also been given DOT approval to begin Atlanta/Shanghai flights.