Yep - Halloween in the Quarter is crazy. I haven't been, but I've seen pics and news reports.
Yesterday (Saturday), I had a chance to go down the Convention Center in New Orleans with a friend of mine who rides in Bacchus. The Bacchus floats were being loaded for tonight's ride, and I was able to walk around and take pictures of the floats. That was a fun shoot and I was lucky to have that opportunity. I shot with the D700, SB-400, and the 14-24mm lens.
By the way, if you don't already own the little Nikon SB-400 flash, get one as soon as you can - it is a terrific little unit and has a tilting head for bounce and it uses 2 AA batteries and recycles quickly. I hardly take it off of the camera, and I have the SB-600 and SB-800.