Kids, 6 & 9, really liked the Kid's Club a lot. There are a lot of counselors and they seem really interactive with the kids. The fact that this is a "nickeloeon" themed cruise should be more or less ignored -- it has little to do with the kid's club, and just impacts a few activities. Overall, the Kid's Club gets 5 stars. Not all kid's like it, apparently, but mine wanted to be in there every possible moment.
The actual boat itself was nice, but relatively unimpressive compared to a big resort (first time cruiser, take my comments with a grain of salt). The pools are modest in size, crowded and salt-water as opposed to just clorinated. The "adult" hot tubs are only lightly heated. The free buffet style cafeteria is a cut above what you would get at say the Disney "All Star" resorts, and while its nothing great, doesnt really warrant complaints. You can usually find a seat pretty easily, except on the first day. The two free sit down places to eat have the same menu as each other, and have 4-5 dinner choices that are the same every day, and 4 or so that are different every day. So not a lot of choices, and the service can be pretty slow even when they are only half full. Not Jamaica slow, but still noticeably slow -- we waited 15-20 minutes for our order to be taken. The views are good though. The pools, hot tubs and places to eat close at some point for the night, so if you are the kind that likes to wander super late, kind of a downer. The sole exception is a 24 hour sit-down option that serves food like hot dogs and hamburgers that you have to wait 15 minutes to get.
Soda is also a problem. First they make you wait in line and buy a soda card for around $50 for a 7 day cruise. (Why cant you do that in advance?) Then they dont have soda machines, they have a single guy serving soda and beer in a cafeteria serving like 500 people at a time. As far as I knew, if you wanted juice, you have to "steal" it from the kid's area.
The cafeteria has a kid's food section with things like mac and cheese, hot dogs, hamburgers and chicken fingers. However, on "chocolate night" they replaced the entire buffet cafeteria for the entire evening with chocolate deserts, AND FORGOT TO SERVE KID'S FOOD SOMEWHERE. We asked multiple employees, and there was nowhere to go for kid's food. We ended up having to wait 15 minutes for sit-down service of hot-dogs/chicken fingers at the 24 hour place. That was a drag.
The shows were pretty good, singing, dancing and acrobat wise, and the hypnotist was good too. I dont think I have ever seen a performer as shockingly flexible as the female acrobat in one of the shows. However, there was wide agreement among passengers that the comedian was perhaps the single worst comedian folks had ever seen.
In general, it felt to us like way to much space & time was devoted to them trying to sell you stuff. More space is given to stuff they are trying to sell than to the pools, or at least it feels that way, and at least half the "activities" are designed to sell you something or cost extra. It really detracted from the experience, just the way going to a hotel and having them constantly hawk time shares would.
The activities were mostly very lame. There are a lot listed every day, but half are trying to sell you something, and many others are lame. For example, one day, "Napkin folding" and "Towel folding" were separately listed activities. Now I dont object if some people are interested in those things, but overall, the activities just held little appeal and/or were lame.
There is very little space for sports. One combo tennis/basketball court. There are 4-5 ping pong tables, but all are exposed to wind, and only 1 was generally used because the others were too windy. The shuffleboard equipment was often locked up, and we had no idea when it was supposed to be available.
The Nickeleon aspect of the cruise is pretty much not worth discussing. There is almost nothing to it -- one "slime time" show which is fun (and repeated twice during the cruise), some characters at random times, and a pay extra breakfast.