For those that are concerned that their kids WON'T like the activities and they'll hear about it all during the cruise, my I suggest something I picked up from the Bill Cosby show?
The idea is probably 13 or 14 years old but on one of the Cosby shows the family was doing something the next day the 13 yo didn't want to do. Cosby told her she could glum around and be miserable that night but the next morning she was welcome to FEEL any way she wanted, however she was required to ACT like she was enjoying herself and be a pleasant person around the rest of the family (or else she was grounded). In other words, she would CHOOSE to be a pleasant person.
I used this on DD when she was 13 for a weekend activity. She "pretended" so well that I think she actually enjoyed herself. I was rewarded when she was 18 by a discussion of the situation. She told me that she was REALLY mad at me at the time but that she learned a valuable lesson and would probably use the same tactics on her kids when she had them.
I think CHOOSING to be pleasant is a great life lesson for our kids. We adults do it all the time at work and other situations. Considering what the cruise costs, no one should make the whole family miserable because it isn't as perfect as they planned.
Just my two cents.