As markets await the Jackson Hole speech for clues as to where Bernanke will take monetary policy, the Federal Reserve released its Beige Book for July and early August which showed ?economic activity continued to expand gradually.?  The Fed?s latest look at current economic conditions came after Wednesday?s updated GDP numbers, which showed the economy expanding at an annual rate of 1.7%  in the second quarter, as opposed to 1.5% in the previous estimate.  While that is an encouraging sign, output is growing at rates that make it difficult to sustain the current unemployment rate.