According to a representative of the New Orleans Convention & Visitor's Bureau, New Orleans is packed this weekend (and we're not even counting the people sleeping outside on the Endymion route). Here are the hotel occupancy numbers as of this morning:
Fri.: 95%
Sat.: 98%
Sun.: 93%
Mon.: 86%
Tue.: 78%
On a somewhat related note, I got a Mardi Gras-themed promotional email from Hotels.com this morning. Do you see what I see?

Yep, it's a sale on rooms at well-known Mardi Gras hot spots like New York and Las Vegas. Maybe given the occupancy rates here at Carnival central, they didn't have any rooms to sell in New Orleans.