For international shipping to and from Europe, that seems significant.
And for southern exports and imports, and for access to the west via the Mississippi, much less so. And since the tables Pea gives us in the #779 link show that 1,918 ships visited New Orleans in the 12 months prior to August 31, 1860 ( a figure that doesn't include steamboats, btw), it's pretty clear that New Orleans was a thriving, major port.