Well, I'm obviously in the minority here, but I had a horrible time on my Norwegian Cruise out of NYC in 2005. A lot of our problems were ones you probably won't encounter (like sewage coming out of our bathroom and a misrepresented snorkeling trip), so I won't go into the details here.
Two things that seemed to be universal:
1. Our cruise was super rocky until we hit North Carolina. This was in early December, so hopefully the weather in May will make your trip smoother, but I will never cruise out of NY again. My husband never gained his sea legs.
2. The food on the Norwegian Dawn was disgusting. We weren't the only ones who thought so. By the time we reached our first port of call everyone on the ship was thrilled to see that there was a Burger King just a short walk from where our ship was docked. It was the talk of the ship for days. Either people were excited to get real food again at Burger King or they were disappointed that they didn't see the Burger King until it was too late to go. By the way, I'm not a fast food eater. I'm not sure I've eaten at Burger King since that trip, but it was much better than the food I had on the cruise.
I've been on other cruises and enjoyed the food. I think it may have been the freestyle eating. Perhaps when chefs don't have an exact head count for each mealtimes, quality is affected.
I hope I'm not too late in warning you about this. In the last 4 years it has become one of my personal missions to warn people against cruising Norwegian Dawn.