One of the reasons why HHC typically occurs near the end of September is because when it was first held 30 or so years ago, it was believed that air travel and hotel costs went down significantly after the end of the "summer season", considered to end September 15th.
Is this still true?
Do costs for air travel and hotel stays go down once you pass September 15th? They may have in the past, but do they still do so?
If not, then perhaps HHC 2011 and beyond might be held in early / late August instead of the end of September.
But, the committee needs data! Help! :-)