You might want to see a AAA travel agent for the best Disney rates. Karen at 1-800-826-7447 takes good care of us.
Once you check into your hotel on the land part, you are registered for the whole shebang. They see that your luggage gets from the hotel to your stateroom. You're pre registered so you just step aboard when the bus arrives at the terminal. If you include air, the service starts when you check your luggage at home.
Sea only passengers think there isn't going to be much of a crowd from the numbers waiting in the terminal. Once aboard you learn that the hundreds and hundreds and hundreds from WDW have gone directly aboard.
Only drawback I saw was that the people from the park, especially the ones who have spent four days, are exhausted when they reach the ship. It's a shame the cruise can't be first.
Again, AAA is Disney's chosen agency. Book with them and you get free soft drinks during the cruise. In fact, booking with AAA and using AMEX will get you a lot of perks both in the park and on the ship.
More than you ever wanted to know.