I assume you own at WLV so book at the 11 mos window to get ressies this time of yr. WLV are VERY popular near the holidays and get booked pretty fast at the 11 mos. If you dont own at WLV, go ahead and book at your home resort and get on the waitlist ASAP for WLV.
We have been to WDW 3times within the first 2 weeks of Dec. 1st trip was warm, no rain, maybe 1 cool evening. 2nd trip was warm, no rain with 1 cool day. Last Dec., awhole different ballgame, cold and rainy. But its WDW, not much can ruin atrip there.
You will love WDW and WLV that time of yr. Its our favorite time at WDW so far. Crowds are down, decorations are up. See Candlelight Processional at Epcot, Osbourne Spectacle of lights at MGM, and go to Mickeys Very Merry Christmas Party at MK. All of these things will get YULE in the mood for the holidays if nothing else will.