We've gone every T-giving for the past 15 years...this year, in the midst of being thankful for such important things as my DS' first "in the real world" job that starts 10/22, I'll shed more than a few tears over not being at WDW...
We've done everything from the Friday before T-giving to the Tuesday after (that was a grand trip!) to "just" Wed-Sun (including T-giving)...
Yes, there are significant crowds...we've never been over Christmas, but we've been for spring break, and for 4th of July...T-giving is the "worst" in terms of crowds (altho it reads like Christmas week is even worse)--
Crowds start picking up the Tues before T-giving and don't start noticeably lightening up til late the Sunday after.
But it's an absolutely wonderful time to be at WDW...everything is all dressed up for the holidays by the Friday after T-giving (and most of the decorations are up well before that); it's the start of the wonderful feelings that come w/the holidays...oh, I am going to miss it, so much, this year! (But I'm so thankful to see my wonderful DS graduating from law school (in two weeks) and gainfully employed and so excited about it! And I'm sure I'll enjoy either him coming home for T-giving or me going to him (New York City--that will be pretty cool too)...
As others have said: get to the parks early (crowds don't start being "intense" til 10:30-11, or even noon)...go back at dinner and after...use FPes...enjoy the resorts themselves...
It's probably not the best time for "commando touring" but it's a wonderful wonderful time for a
DVC trip!