You'll be fine unless I spot you and decide that I need 10-20 new lenses
I go to the quarter frequently and there are always tons of people out their with cameras, I have even seen quite a few pentax shooters out there. Even at night, the only thing I really worry about if I go out there is someone accidentally bumping into me.
NO has a reputation as dangerous because of a high murder rate but that is heavily concentrated in a handful of neighborhoods where no tourists visit and is basically rival crews beefing over petty crap and they have no respect for their lives or their neighbors lives. Its tragic, but it is a safe city, I have lived here most of my life and have never felt scared of violence and don't even own a gun.
If you like wildlife photography, there are also plenty of shooting opportunities if you visit some of local wild life preserves or take some of the swamp tours and there is also a great zoo, aquarium, and insectarium. For flowers, there is a botanical garden and sculpture garden at city park as well as longue vue house and gardens. The french quarter is great for street photography and if you go down to the frenchmen st. area, there are lots of great bars with live music like the spotted cat, DBA, the dragon's den, snug harbor, and blue nile to name just a few of my favorites.
Have fun and bring lots of money to spend