Just by reading the post from people just coming back from WDW and CM, Safari Steve's, observations, it looks like the FTP didn't increase the attendance that much, if any. I think what may have happened, is that over the last few years, WDW has offered discount packages during the value season(Fall Fantasy, etc.) and also room only discounts for the same period as the FTP is now being offered. Since room only rates were not offered for Sept., we read several "discussions" about leaving the AP people out of the mix. It appears that the FTP attracted the same number of people as past packages, but WDW upset room only people(AP holders).
This is just a guess, the WDW people may have figures showing the FTP was a huge success.