There's a difference, a song gets on the radio by being released on "adds dates." On these days (always tuesday) the song is sent to radio stations of a certain format (Pop, Adult Contemporary, Alternative, Urban). These formats are generally the songs target audience, Pop having the largest audience. While FOB's single was sent to both Alternative and Pop, Now was only sent to Alternative (where it has actually outperformed FOB). Still Into You hasn't been released to radio at all, but it will be the first official POP single. It doesn't have an adds date as of yet.