Do you really think the week after Thanksgiving would be less crowded than the first week of December??
I was thinking it would be crowded with leftover Thanksgiving vacationers.

Our dates are flexible. Maybe we should consider Nov 27th - 29th??
Are the Christmas decorations up then?
I subscribe to TouringPlans.com and here is their historic crowds numbers for 2011:
DLS average DL DCA
Mon, November 28, 2011 3 out of 10 2.2 2.6
Tue, November 29, 2011 3 out of 10 2.0 2.8
Wed, November 30, 2011 3 out of 10 2.6 3.4
Thu, December 1, 2011 3 out of 10 2.6 3.2
Fri, December 2, 2011 7 out of 10 7.2 5.0
Sat, December 3, 2011 8 out of 10 7.3 6.9
Sun, December 4, 2011 7 out of 10 7.4 6.5
Mon, December 5, 2011 5 out of 10 4.3 4.8
Tue, December 6, 2011 5 out of 10 4.1 4.9
Wed, December 7, 2011 5 out of 10 4.6 5.1
Thu, December 8, 2011 7 out of 10 7.2 4.0
Fri, December 9, 2011 8 out of 10 8.4 6.4
Sat, December 10, 2011 8 out of 10 8.2 5.7
Sun, December 11, 2011 8 out of 10 6.8 7.2
Mon, December 12, 2011 3 out of 10 2.4 5.4
Tue, December 13, 2011 3 out of 10 2.1 5.3
Wed, December 14, 2011 7 out of 10 7.4 5.3
Thu, December 15, 2011 6 out of 10 5.5 5.3
Fri, December 16, 2011 7 out of 10 8.0 5.7
Here is what they are projecting for 2012:
Mon, November 26, 2012 3 out of 10 2.7 4.2
Tue, November 27, 2012 2 out of 10 1.5 4.3
Wed, November 28, 2012 4 out of 10 3.7 4.8
Thu, November 29, 2012 3 out of 10 2.9 4.5
Fri, November 30, 2012 8 out of 10 8.8 6.1
Sat, December 1, 2012 8 out of 10 8.5 6.3
Sun, December 2, 2012 9 out of 10 9.2 7.8
Mon, December 3, 2012 7 out of 10 7.5 6.1
Tue, December 4, 2012 7 out of 10 6.7 6.2
Wed, December 5, 2012 8 out of 10 7.9 6.5
Thu, December 6, 2012 8 out of 10 8.5 6.5
Fri, December 7, 2012 9 out of 10 9.8 6.9
Sat, December 8, 2012 9 out of 10 9.4 6.9
Sun, December 9, 2012 9 out of 10 8.7 8.0
Mon, December 10, 2012 4 out of 10 3.5 6.3
Tue, December 11, 2012 4 out of 10 2.5 6.3
Wed, December 12, 2012 9 out of 10 9.1 6.4
Thu, December 13, 2012 8 out of 10 8.9 6.6
Fri, December 14, 2012 9 out of 10 9.4 6.5
Sat, December 15, 2012 7 out of 10 7.7 6.3
Sun, December 16, 2012 8 out of 10 8.0 7.9
Mon, December 17, 2012 8 out of 10 8.5 6.5
Tue, December 18, 2012 8 out of 10 8.3 6.6
Wed, December 19, 2012 9 out of 10 9.0 6.7
Thu, December 20, 2012 8 out of 10 9.3 3.3
While they have been adjusting their predicted based on larger crowds at DCA, I think it will be busier then it has been in the past.