Our daughter was 8 months old when we cruised in January and I am at home with her. Flounder's was nice, I felt pretty good leaving her, it's Disney you know! This was the first time I had left her with a stranger. You have a pager and you can drop in to check on your child (I did this without her seeing me for my own peace of mind) and there are passengers in and out frequently. They will accommodate any special requests. Toward the end of the night and the end of the week, many children had figured it out and were fussy. I definitely recommend doing Palo's early in the week.
There are more than enough cast members to staff the nursery and I think it would be next to impossible to do something dangerous or inappropriate. The cast members "volunteer" to work in there from what I understand and several have children back home. They were holding and rocking the children.
Have a great trip!
Susan