To give you some background, this was our 5th cruise with Carnival and 6th overall. We cruised with our three children, 12, 8 and 2 years old. We were also traveling with my parents and a married couple that I work with.
Embarkation: We boarded around 1pm and everything went very smooth. No long lines to wait in, with the exception of about a 10 minute wait to get our embarkation photo taken. Our last trip out of Miami was back in 2003, and the port has definitely improved. One thing I will say, is that for $20 per day, the parking should be covered. Other ports in Florida are less expensive, but offer covered parking. This is certainly not Carnival's fault though, it's a Miami Port Authority thing.
We went straight to the Lido deck for a drink and some food. We were supposed to set sail at 4pm, but did not actually leave until 5:45 or so. I had to choose between staying for the full Camp Carnival orientation or going up on one of the top decks to watch the sail away. Fortunately, having cruised Carnival many times with the family, I was able to leave orientation without missing much. I do feel bad however for those that did not have that previous experience and missed sailing away from Miami.