My wife told me that the Buggles song was the first to air MTV, but I think the longest playing was "Oh, Mickey", from Toni Basil! (More useless info...The keyboardest is now one of the members to 'Asia', and the singer went to make the group 'Yes'.)
However, MTV seemed to be the perfect tool to expose the "New Wave Music" for the likes of Boy George, Duran Duran, Adam Ant, etc.!