Caryn,
My wife and I are sailing on the Paradise to Catalina/Ensenada on 10/27/08. We have done this cruise 2 times before. The first was in the month of October and the weather was nice (in the high 70's to low 80's). The second trip was in December 2 years ago, and the weather was in the high 70's. During the day when the ship was in port, the weather was fine and no jacket required, but walking around the decks when the ship was moving could get a little chilly. Especially when the sun goes down. We recently did back to back cruises the last week of December and the 1st week of January (got married before we sailed) to the Mexican Riviera. The weather was wonderful both weeks. It did get cooler the closer you got to Long Beach.
If you are coming in the night before the cruise, a good place to stay is on the Queen Mary (right next to the cruise terminal). If you tell them you are cruising on the Paradise and would like their cruise rates, you can get a nice room for $119 a night.
Hope you enjoy your cruise.
Chuck