The entertainment was phenomenal! We have been on 3 other cruises (2 with Carnival) and to Vegas in the last 4 years and still thought that the production shows were among the best we've seen.
The food was average by cruise ship standards, I have learned to stay away from the buffets because of the crowds and likelihood of getting cold food. I much prefer the dining room, especially for breakfast and dinner. We ate at Johnny Rockets a few times and the sandwiches were great (try the apple pie a-la-mode also) but beware, it can get crowded.
One problem that someone else had mentioned, was the chair saving at the pool. We found 2 chairs at around 9:30 and stayed there until early afternoon. There were towels and a bag on the 2 chairs next to us when we got there. When we left around 2:00, the owners of the stuff hadn't come to claim it or use the chairs. (At around 12:00 we told some folks to take the seats and set the stuff aside, because no-one had shown up) I'm not sure how to prevent people from being rude and inconsiderate but pool chairs became a scarce commodity.
We did not notice any problems with children as was also mentioned, but we hung out near the adult pool during the "at sea" days. Overall, the cruise was great, beautiful clean ship, (all 3 of our other ships were new when we sailed on them) very good service and excellent entertainment.