We took our first trip for Thanksgiving this year and I thought it was a great time to be there. I guess it's all a matter of perspective, but I didn't think the crowds were any worse for most of the trip than in early summer when our last few trips have been.
We had a late flight down on Tuesday of TG week and left early the following Tuesday. That Wednesday was really the only day I felt it was worse than we were used to. We were at DHS that day and stood in line for the GMR for 45 min! Everything else we had FP's for, including being able to grab FP that day for RNR and TOT and Star Tours twice. We had the 3 prebooked....but were able to add more as used with a little work on checking constantly. Thanksgiving we started at AK for a few rides the kids wanted to do, then hopped over to Epcot for our FP's and dinner ADR. The rest of the week I didn't feel it was terrible holiday like crowds, except DTD. Went there on Friday and it was busy. You could hardly move in the walkways some times. Saturday we spent the am in MK, did quite a few rides in the time we had, then hopped to Epcot. It may have been a little crowded, but we had short waits and FP's for what we wanted to ride. That evening we had a dinner package for the CP. We really just spent that evening at Epcot seeing the holiday stuff, CP show, fireworks, etc.... but in between we did manage to ride the few things we wanted to. On Sunday the crowds really thinned out. We only did the Christmas party that day, so I don't know what the other parks were like. MK was rather crowded, but we entered just after 4 and had FP's for a couple rides before our dinner ADR. The Monday after Thanksgiving was the best day. We started at HS for a breakfast ADR, did our favorite rides, hopped to Epcot, did our favorites over there then hopped again to MK in time to see Wishes. While talking to the CM working the ferry dock, he commented that day was the smallest crowds he'd seen in weeks, that the Monday and Tuesday before Thanksgiving was insanely crowded.
So if we ever go at that time again....which I'd love to, I'd definitely recommend getting in just before Thanksgiving and staying beyond the weekend a few days. I was trying to maximize our trip length without having the kids miss more than 2 days of school and it worked out perfectly. We've been several times over the last 10 years....but this trip was one of our favorites.
regards