Princess seems to have added some 7 day cruises out of San Diego. The prices for this particular itinerary looks very good, especially in October. From U$499 for an inside cabin. San Diego is an easy airport to fly into (okay, it's a bit scary, but still the prices to fly into San Diego are great.)
If you want to see, just go to Google Maps and you can see how close the airport is to town. That's right, one runway and it backs to a major intersection. Quite something to see the planes land and take off.
Incidentally, the cruise port is REALLY close to the airport. Don't bother with the cruise company transfer, just grab a taxi.