While at WDW last December, we decided to resort hop to see the decorations. We saw Board Walk (we stayed here), Contemporary, Polynesian, Grand Floridian, and Wildnerness Lodge. I honestly can't say that one was better than the other because they were all themed for the resort. If you want a Victorian feeling, then GF is the place to be. But Boardwalk is a very close second with a Victoran Seashore feel. If you want rustic lodge, then there's no place like Wilderness Lodge. The Contemporary was just that, "contemporary." It's not my style, but it worked very well for the resort. The Polynesian's decorations were beautiful as well. They used tropical flowers in their decorations instead of the typical poinsettia and holly.
I really think it depends on your tastes and what Christmas means to you. I loved all the resorts we visited for different reasons. I say stay at the one you typically like the best and visit the rest of them!!!