http://old.mises.org:88/NO2 is the only webcam I know of in the city - the cam is run during daylight hours from directNIC which is located in downtown NO, a few blocks south of the Superdome. The hosting company is running on generator and being kept secure by their emergency management.
http://sigmund.biz/kat/index.html has the archives of both the cam and camera shots taken from just before the hurricane to today. (it takes quite a while to load unless you have wide broadband.)