Help-which week would be better w/baby & 2 older kids-After T'giving vs. 2nd wk Dec.?

[loveysbydesign]

We took our 1st family trip to WDW this past May and loved it! We're hoping to go again late in '07 but will have a 5-6 month old baby as well as our 2 older kids, they'll be 8 1/2 and 5 y.o. I was wondering if it's better to go the week after thanksgiving or the 2nd week in Dec. I'm trying to see if there's much difference in the weather, crowds and airfare prices.
If any of you were there this past year for either of those weeks I'd love to hear your experiences!!!!!

 

[belle&beast]

I'm curious, too. I would love to go in early December because of the Christmas decorations, but I don't know the answer to your question.