We have no experience (yet) at
DVC...just bought...but we were told when we bought how hard it is to get reservations during holidays (and we like to go at T-giving)...from reading Disboards, it seems it's also hard in Oct & December...
Anyway, in mid-June I made reservations for us at SSR for T-giving (Wed-Mon)...got Fri-Mon, but not Wed-THurs...we went on the WL and I had almost no hope...but, today we got notice we are off the WL and in! We got a 1-br rather than a studio, but that is a-ok w/us...yes, they are more points, but worth it to us and we requested any studio or any 1 br at any resort for those two days...we're thrilled to be at SSR the whole trip (would have been willing to move between resorts, but sure am glad we don't have to!)...
So...while Disney will tell you (repeatedly) that there are no guarantees, we're "proof" that it is possible...especially if you can be flexible about resorts, or even about size of accommodations (MS told us studios & 1-br's were actually more available than 2-br's and GV's...cuz of "family time planning" at holidays)...
I started a "what are the chances" thread when we first went on the WL...several Disboarders sprinkled pixie dust at us...it worked (and I thank them), so here's a load of pixie dust for you!