Winter 2009 had some of Disney's more generous deals. There was
free dining (QSDP at values,
DDP at mods & deluxes), Buy 4 Get 3 Free at mods & deluxes & Buy 5 get 2 Free at values and I think there were room discounts as well. These were released quite late by Disney standards and were seen as a last ditch effort to fill rooms that just weren't filling. I would NOT count on seeing deals like this year. It may happen but it'll once again likely be a last ditch effort to fill rooms like last year if it happens at all. Do not count on it and you won't be disappointed.
Mousesavers has a very useful list of historical data regarding past offers.
http://www.mousesavers.com/historicalwdwdiscounts.html