If the media can get in there and take pictures, and they can land helicopters to take the sick away (though those have been suspened now due to an alleged shooting) surely they can find a way to start getting water and some sort of food or something in there. And if they can bus people out they should be bringing supplies IN on the busses that are coming in to pick people up.
The reason people are starting to riot is because they're desparete and have no food or water. Don't they think that the situation would improve if they helped the people while they are waiting?
Yes, I know 60,000 people is a lot. And if you start bringing in supplies and there aren't enough you risk a real riot. But come on, you have to at least try. There has to be something they could be doing.
EDIT: Latest update from CNN - Mayor is issuing an urgent "SOS" for the people trapped at the Superdome:
http://www.cnn.com/2005/WEATHER/09/01/katrina.impact/index.html