There have been a lot of posts on here about how annoyed people get by walkie talkie use. This last cruise left from NYC and everyone was up on deck watching us sail out of NY (an awesome experience). As we were up on the bow, gliding quietly by the SoL, etc., all I could hear were the walkie talkies: "where are you? Statue of Liberty is right here! get up here! here! up front! can you hear me?" etc. I have been very mildly annoyed by them in the past but just tuned them out. This time it was really bad. The thing is that IME no one ever uses them by Day 2 or 3. Believe me, 12 year olds will know where you are at all times. They are on a mission 24/7, checking out what's happening, where everyone is, what's going on. And by the 2nd or 3rd day you (hopefully) will be so chilled out you won't care where anyone is.
Post its are a great idea. You can leave messages for the cabin steward as well. But the walkie talkies are intrusive and unnecessary. You are within hearing distance of many people at all times and IMHO there is no need for them.