This was our second cruise, both with Princess and our first being Alaska in May of 2006.
We went down a few days early and visited the local beaches and Hollywood, very easy to get around LA on your own. We stayed at the Doubletree in San Pedro before and after the cruise. They offered free shuttles to the cruise ship terminal and will pick you up when you get back. I would not recommend this hotel as on both occasions our bathrooms were extremely dirty and not cleaned properly.
Embarkation was a breeze when considering 3,000 people were about to board the ship. We arrived around 1130, checked in promptly and were asked to wait about 15-20 minutes before our number was called. Princess gave out numbers according to the time you arrived to ease check-in and security screening. We were onboard, dropped off some bags in our room and sitting at the pool shortly after 1230pm. We had a balcony cabin midshape and it was wonderful, we saw dolphins and had multiple whale sightings on our way to Puerto Vallarta. The Diamond is only a few years old and a beautiful ship. I found the atrium and entertainment rooms to be much smaller than the Dawn which is a smaller ship. The ship is in good condition and well taken care of. Our cabin storage was nicely laid out and provided plenty of closet storage as well as room under your bed for your suitcases. Our balcony was good sized, I would recommend the Baja or deck above if you want a balcony as the onces below are terraced and offer no privacy.