I was reading an article on Travel Weekly on ships pulling out of South California. Although there are many pros for cruising from California: year round sunshine, excellent pre & post cruise options (Disney, San Diego Zoo, etc)...the state was the hardest hit in the recession and is slow to recover. Rates have plummeted and it takes a lot of fuel to even get to the first port so it really wasn't profitable anymore for the cruise lines.
Both Carnival & Royal Caribbean are moving, but there is still some good news. Disney will be stationing their newest edition, Disney Wonder in L.A. Crystal Cruises does cruises up & down the west coast. Princess has round trip cruises to Hawaii, as will Holland America. As the economy picks up, there's no telling what's in the future for south California.
Personally, I think that after a year or 2, they will flock back to the area.