In A Few More PivotTable Improvements in Excel 2010, Diego Oppenheimer, Program Manager on the Excel team at Microsoft, discusses new pivot table features being implemented for the next release of Excel.
One of the improvement mentioned is the ability to repeat down labels to facilitate using formulas with the pivot table as a source. If you don't want to wait for the next Excel version, here's a trick to get to the same result.
Spotting Errors