Oho! WE HEAR that model-heiress Lydia Hearst has been shunted aside at Page Six magazine to make way for a similar gal-about-town column by 17-year-old soap star Leven Rambin. Wonder what she thinks of the subway fare hike? Update: Oh, ok, Lydia is "not fired," it's just that Leven will have a column also. The more the merrier.