My wife and I are both in our late 50s. This was our second cruise, the first being on Carnival Imagination in February 2008.
Embarkation: We live about 3 hours from Miami and drove to the port on the day of the cruise. We arrived around 11:30. Traffic dropping off luggage and passengers was somewhat daunting but porters were extremely easy to find and helpful. After showing our E-docs and passports, our pictures were captured and we were given our sign and sail cards. We were aboard by 12:15. The process as compared to Carnival was roughly the same.
Cabin: We were in an inside cabin, 10009, on the forward starboard side. The cabin is smaller than Carnival's, which was expected since we had a balcony on our Carnival sailing. There was plenty of storage space and the layout of the bathroom in the Dawn was superior to that of Carnival. One minor irritant was that it proved difficult to keep the bathroom door shut. You have to close the door firmly and jiggle the handle to make sure that it catches. I'd have to give the nod to Carnival for bed comfort. This isn't to say that the Dawn's bed is bad, but rather that Carnival's was better. The room was kept spotless and towel animals were provided every night.
Dining: Carnival gets a decided nod over the Dawn in terms of food. You won't go hungry on the Dawn and there was always something on the menu that we'd want to eat, but our recollection is that Carnival had more variety on its menu and that Carnival's execution was generally better. We ate in the main dining rooms Venetian and Aqua every day and in the Garden Cafe for breakfast. In addition on the final sea day, we went to the "Big Band Brunch" in the Venetian which had a surcharge of $15 per person with an additional charge of $5 per drink. So, $20 per person for brunch. I'd rate it as worth the surcharge but only marginally so.
We liked the Freestyle dining where we could eat any time we wished. With the exception of a short 5-10 minute wait at the Aqua on lobster night, we were always seated right away.
Service: During our trip with Carnival, we were greatly impressed with our steward. Maria and Arnel, our stewards on the Dawn, managed to easily clear this very high bar. They were superlative. Indeed, with one very minor exception (a waiter in the main dining room who wasn't familiar with one menu item and whose service was otherwise excellent), every crew member with whom we interacted was friendly, helpful, pleasant and professional. Carnival's staff was fine, but we'd have to say that the Dawn's staff exceeded that by a substantial margin.
Entertainment: For us, the onboard entertainment of the Dawn blew Carnival's away. The Welcome Aboard show for the two ships were roughly about the same. My DW didn't particularly care for the headliner comedian the second night but he was getting laughs from the audience. The magician on the third night was excellent and we made a point of seeing him do card tricks on the fourth night. The "Bollywood" show on the fifth and final night was a Cirque d'Soliel type of show that we both loved. It was far, far superior to anything we saw on Carnival. Second City, the famous improvisational comedy troupe, also performed, but we did not attend. In all of the above shows, we attended the early 7:30 one and it appeared that seats were always available.
Activities: Shipboard activities during the days at sea were roughly equivalent. My wife and I are both trivia fanatics and the Dawn ran two or sometimes three games per day. We also got the spa pass which, at $75 dollars per person has apparently been increased. We were kept so busy however, that we didn't get a chance to use the spa that much. I think the next cruise we'll probably give the spa pass a pass.
Casino: The casino staff was friendly and cheerful but the casino often had little traffic. This might be a function of high minimum table games. The craps table with a $10 minimum was often deserted with the dealers waiting forlornly for business. Many of the blackjack tables had $15 minimums and the $5 table (which was usually the busiest) had terrible rules: 6-5 payout for blackjack. It might be profitable for Norwegian to consider knocking down the minimums a bit.
Ports: We stopped in the Grand Cayman and Cozumel. See my port reviews below.
Disembarkation: Disembarkation was about as easy as it gets. Just select a tag color for your luggage that corresponds to the time frame you want to leave, slap it on your luggage and leave your bags in the hall on the final night of the cruise.
As I always do, I picked the wrong line to stand in. A party ahead of us apparently had not settled their bill prior to debarkation and held the line up for a few minutes but after that, we breezed through customs, found our bags immediately and were in our car and on the highway about 20 minutes from the start of the departure process.