Totally depends on what the offer is and which resort you book.
In general the most recent permutation is value resorts getting the quick service plan free and moderates/deluxes get the regular plan free. That may or may not be changing. There have already been changes to the frequency of the offers this year, as no general public free dining at all was offered for the January-February time frame. All current offers that include dates in 2013 have come from either PIN codes or bounceback offers.
I read a post on here yesterday that free dining for UK residents, which was previously quick service at moderates and regular dining at deluxes, is now quick service at all resorts (except values - UK doesn't get free dining at values). So are changes coming for any US public offers that may come out? Possibly, there haven't been any yet, so we can't say. Lots of rumors going around.