As an addendum to my original question:
What promotions from the cruise industry would encourage passengers to cruise even with higher airfare and/or cruise costs?
Aggressive upgrade program
Price reduction for the basic cruise
Special promotions - such as discounted or free excursions
Free drinks and or free or reduced prices at specialty restaurants
On a personal note -- we were going to take a cruise this December as we have the past number of years. Airline travel is becoming so expensive for us that we are considering an all inclusive vacation to the Mayan area or Hawaii to defrost.