This is very interesting. Bill Tancer at Hitwise maps search query trends against economic indicators. Using this method, he claims to be able to detect which way trends will go in the near future:
“Aside from the excitement of discovering this indicator, the other good news is, barring any unusual circumstances over the next week, our search term data indicates a reversal in the downward trend reported by NAR yesterday. The August numbers, scheduled to be released September 25th, should reflect that reversal. Mark your calendars”
I will. And report back then.