The biggest secret at RCI and at the building shipyard is what the Genesis ships will have on them. There are rumors but nothing factual. They even made everyone involved sign secrecy agreements. You cannot pry anything out of anyone. All I was told - by Bill Wright who is senior VP for operations - is "game over". I assume that to mean nobody will top the Genesis ships.
Bowling alleys are not new. NCL has at least one on a ship right now.