This is my recent experience with a waitlist.
I called on June 13 about making a reservation for a 1 bedroom (basically at any resort available) for December 27-January 1. I had called a few days earlier and was told NOTHING was available anywhere. Somehow, the CM from Member Services was able to find 2 nights in a 1 bedroom at SSR and then 2 nights in a 1 bedroom at OKW. Nothing for New Year's Eve.
I went on the waitlist for a 1 bedroom at Saratoga Springs for the whole stay and also on a waitlist for a 1 bedroom standard view at Kidani. I was told to call back periodically as it might increase my chances. I never did.
On July 14th, my waitlist for a 1 bedroom at Saratoga Springs went through for the whole stay, including New Year's Eve. I found this out by looking at the
DVC member site. I was glad to just have a whole vacation at 1 resort and all the nights I needed.
On July 21st, my waitlist for a 1 bedroom standard view at Kidani went through for the whole stay as well, cancelling out my reservation at Saratoga Springs. I also found this out by going on the DVC member site. I was surprised because I thought since I already had a waitlist come through that all my waitlists would be cancelled out, even though I wanted to stay at Kidani more. I guess this was not the case.
This was only my second time using a waitlist and both times it has come through for us, so I was pretty pleased, especially since it came through so quickly. Both CMs I spoke to at Member Services made it seem like it would be impossible for me to get the nights I needed, particurly for New Year's Eve.
Good luck!