It was first reported here:
Many Evacuated, but Thousands Still Waiting(still no state of emergency in LA) ^
She DID declare a State of Emergency. What she hasn't done is declare it a disaster area.
I think that you may be right, she has not allowed the Louisiana to be declared a national disaster area, which would open the door for federal assistance.
My husband will be headed down to the area as a volunteer in the oil spill clean up effort and I hope that he doesn't get sent to NOLA and have to be directed by their state officials. That would be a nightmare.