We took a shuttle bus that we caught at the Miami airport. We didn't book ahead but later found out that the county will only let people ride shuttles that pre-book them to protect taxi drivers. The shuttles will take you anyway obviously as they want business but run the risk of getting fined. So they will ask your name and put you in their log in case you go this route and are wondering why they are asking your name. It was $9pp each way which seemed to be the going rate for shuttles. It's $20-25 for a cab ride as we understood it. And I think Carnival charges $16pp each way. So those are the options.
Embarkation: We got there around 2pm and it was quick and smooth. No problems.
Stateroom: We had an interior room on the 7th deck. It was clean and not a lot of frills but fine. Our stewards did a great job. Someone else mentioned this and I will too. Remember the walls aren't made of steel and noise can travel through those hallways if you catch my drift so beware.