You either had a Disney Visa Offer, an email pin code offer, a post card pin code offer, or there was a pin attached to your name in the WDW data base that allowed you to receive the free dining discount when you booked your November 2008 trip. There was no general public free dining offer in November 2008. You can confirm that on the Codes and Rates Board here on the DIS or Mousesavers.com or ask Dining Moderator TDC Nala.
As I stated earlier, I have never received a PIN offer, but did have free dining in November of 2006, 2008, and 2009. MouseSavers does not say specifically that the Disney Visa offer that opened on 8-14-06 and became open to the general public on 8-17-06 included free dining. I know that the stay, play and dine package was available that year, possibly ending before November. If that was the case, then the Season of Dreams Fall package offered fairly large discounts that would have covered, or nearly covered the cost for us to add on the dining plan for two adults and a child.
In 2008, there was a package "free dining" Disney Visa offer made available on 9-18-08. (Can be found on Mousesavers.com) This package deal also included up to a 20% discount on some of the rooms. I do know that there were people able to book the package using the Visa code who did NOT have a Disney Visa card. Guess it was dependent on the CM that the caller got.
In 2009, The free dining offer that included November became available to Disney Visa holders on 7-24-09, and became available to the general public on 9-27-09.