They should be up . .it's why I planned the timing of my trip around the same time (10th -16th) ----- to see some of the Christmas decorations!
If my research is accurate, your trip will have the decorations up at MK, they will be filming the Christmas shows at the parks that weekend after you arrive and the decorations should be up at Disney Springs and DHS as well.
Epcot will still be doing Food and Wine, so not sure if they will have Christmas Decorations yet (or what they do for that).
Plus, due to going back to standard time (this weekend), it should be darker earlier --- to see any lighting effects for Christmas (or the Christmas shows)
Should be a fun time! "See" there! LOL.