We were there last year from the 11th-18th. Gingerbread display was up at Comtemporary. The gingerbread house was up at GF, but not "open for business", and Epcot resorts were being decorated as we were leaving. Poly was not decorated yet.
MK was decorated. AK was as well. HS was, but they moved fast b/c of demand for Osbourne Lights, EPCOT was going up on the 17th, they do not put anything up there until Food and Wine is done.