Re-imbursed for a trip taken on Feb. 29th, 2008?

Several things that will make a difference. If NWA gave control of your ticket to Delta ( rule 240) Re booking for canceled delayed or misconnect you should be dealing with Delta. Once NWA re booked you as a confirmed Penger Delta is the responsible airline and trust me NWA payed plenty to confirm you on that flight. I would request a full refund for expenses and the flight as you missed your cruise. It may take a letter to a VP but it is the contract of carriage.