I can tell you are soooooo excited, triumph!!
There have always been singers (of one type or another) on any Carnival cruise hubby and I have been on. We've seen comedians (those are usually some of our favorite shows), broadway-type musical shows (well, okay, maybe off-broadway!), magic shows, we've even seen ventriloquist shows. Something I think they've started fairly recently, is where passengers audition during karaoke for a show where they perform, but "as" someone famous, like Frank Sinatra, Michael Jackson, Cher, etc. Sometimes the talent is quite good, sometimes not so much so, but we really enjoyed it, nonetheless!