When we were there in Nov '06 (on points), we were offered Bounce Back. There was a card, I believe, in our our Welcome Home package at OKW that outlined the details.
You couldn't use it for a DVC points stay, of course, but you could pay cash and get free DDP if you wanted. You had to be staying onsite at the time of booking (which was a limited period in November and maybe December), and you had to personally go to sign up at one of a couple of locations -- I want to say PORFQ and BC.
We weren't interested in it, but I know a number of DVC/DIS folks did take advantage of the offer.
It was a promotion last year offered to people staying on site, during I think November and December. You could book your next stay, during the free DDP timeframe earlier than the promo became available to the general public.