I'm excited that we might actually be there at that time too amee!
From our previous experience and to concur with Mimi Q, avoid MK on Thursday. We went to MK in '99, arriving late in the after, about dinner time. Main Street was packed for the earlier of the two MSEPs (Spectromagic is there now) and we could barely cross from Tomorrowland to Adventureland. It wasn't until we were in the middle of the conjestion, at the tail end of the parade, that I realized we should have gone around through Fantasyland.
We opted to have our Thanksgiving dinner on Wednesday night when I couldn't secure a PS time for Thursday at the restaurant of my choice. We have a quiet character meal at LTT, during the 4pm seating (the first of the dinner seatings). It wasn't crowded, just us and one other family in our section.
We were in WDW from Saturday evening before through the Saturday morning after. We weren't in the parks either Saturday and went to Daytona Tuesday morning. We didn't feel that it was terribly crowded during our stay, nothing unexpected as far as the number of guests in the park and length of wait times. I'm looking forwarding to returning that same week because we get to enjoy the parks as they transform to the holiday decor and the weather was perfect during our last trip. (hoping for more of the same this time).