Still hoping to for that hard to find ADR?
If your perfect reservation is not available at first glance, keep trying! People do cancel reservations. One key time to try is 45-50 days or so before you hope to dine. For Disney package holders, final payment is due 45 days prior to travel. Many people use that as their "do or die" date and if they opt not to travel, many will cancel their resort and dining reservations all at once. That is your chance to swoop in and scavenger for some good finds!
Right now is a great time for late November and December travelers to look for those hard to find reservations. The Candlelight Processional packages were released yesterday and many people are cancelling their "backup" ADR's.
Finally, keep tabs on the Monthly Cancellation thread over at disboards.com. Nice people over there post when they are cancelling their reservations which will allow those "in the know" the best time to time their dining searches.
Good luck...and happy dining!