Have to agree with others...we have been 5 times in the first two weeks of December and they are some of our most favorite trips! Everything is decorated, uncrowded PLUS to may have the opportunity to go to Mickey's Very Merry Christmas Party....one of my MOST favorite special events!
I have also been twice during Christmas week and don't care to do it again. Tons of people....to the point of being obnoxious, restaurants are crowded, and usually by that time the decorations are getting to the point of being a little 'shop' worn. They've been up a month after all!
Take the money saved and upgrade your resort, try some new restaurants, take an Illuminations cruise, buy that expensive souvenier you've always wanted....whatever works for you! SPLURGE and have fun...you'll be glad you did!