I highly suggest spending the night in Honolulu the night before your cruise. If you stay at the Marriott, you get to proceed to the front of the line which is a great perk.
We were some of the first 25-30 people onboard. Our rooms were not ready so we went upstairs to eat. We checked our carry-on bags with reception (they even locked up our wallets in the safe), hailed a taxi, and went to see Pearl Harbor. I had heard horror stories about huge lines but they weren't bad at all. We still even made it back for the mandatory boat drill at 5:30pm.
Entertainment: The shows were ok. The sets and talent were not as impressive as I have seen on other ships. But, I have cruised a lot and I am a Broadway junkie so I am used to top-notch talent. The best entertainment came in the form on the cruise staff. They were hilarious. Their unending is what kept the ship afloat. Major Kudos to Silas, Don, Greg, and Nick! Make sure you go to the Crew Talent Show the last night onboard to see these guys in action. I was more impressed by the talent that night than by the Broadway style show or the "On the Radio" show that the ship's "performers" performed.
Rooms: I was prepared for our room to be small. Thank goodness we had a balcony though. We had a group of 15 staterooms. 1/3 of our rooms did not have air conditioning. Ours did. But I had 2 staterooms on the inside that didn't. It was incredibly hot. They actually braved it and slept with their doors to the cabin open all night because it was so stifling.
Food: The food was ok. The lines were what EVERYONE was frustrated with. When we got onboard, there was Germ-X everywhere. They spray your hands every time you get on and off the ship.
The lines to eat were incredibly long because in the buffets, people were not allowed to touch anything. The crew were the only ones allowed to touch the food until it got on your plate. After two days, they lightened up and withdrew the restrictions.
We had to wait anywhere from 30-40 minutes to eat at the two main dining restaurants. So, we made reservations at the Kahili one night. We had reservations for 8pm. We were seated at 8:45pm. They apologized-blaiming the people that were seated at our table because they didn't have air in their cabin. They wanted to stay at dinner a little longer to enjoy the cool.
Itinerary: NCl is definately the best way to see Hawaii. As you hear it proclaimed all week, it is the only way to see a different spot everyday. It provided a great comparison of the islands.
Excursions: the best piece of advice is to look at the ship's excursion booklet, then rent a car and do it yourself. We saved lots of money that way. My favorite thing we did was in Kona. Take a $5 taxi to Turtle Beach. Rent your snorkel eqipment there and snorkel off the beach for $8.50 a person. I saw more kinds of fish that I did in the paid excursion in Maui and that one was supposed to be one of the top ten in the world. So, go figure.
All in all, I would do it again. I would just come with less expectations and maybe bring a fan.:)