I think it's a shame they are too young to appreciate the opportunity they have been given. Many adults would give their eye teeth to do what they do.
A friend of mine was a child actress and starred along side the likes of Tommy Steel. She says at the time she didn't realise how famous these people were. I sometimes get the feeling that little Ant & Dec are like that, they sometimes look like they don't have a clue who they are interviewing.