JohnnyR -- not the same situation. You'll have to explain to me how playing a game of chance is the same as making a hotel reservation with a discount code. I don't see the linear thinking there. Except perhaps that some people are getting these discounts and others are not.
Disney very clearly reserves the right to change the rules with their reservations at any time for any reason they choose. And the MOST they owe you if they do -- is a refund of any monies paid. Period.
Any individual would have a hard time persuing this with a lawyer cause it's just not worth it..
As for class action status, you might have more luck there.. but the bottom line is Disney booking policies would be the 'legal contract' you agreed to when you made the reservation... And I can assure you those policies favor Disney and not you and I.
And on top of that.. Disney goes even further by saying that their cancellation and reservation polices are subject to change without notice and at anytime.