1. A system for allowing an operator to update characteristics of an interactive television program guide implemented on a user's user television equipment, the system comprising: means for allowing the operator to supply a first markup language document to the interactive television program guide without intervention by the user, wherein the first markup language document indicates first characteristics of the interactive television program guide; means for generating and displaying a first display screen of the interactive television program guide having the first characteristics as indicated by the first markup language document; means for allowing the operator to supply a second markup language document to the interactive television program guide without intervention by the user when the operator desires to update characteristics of the interactive television program guide, wherein the second markup language document indicates second characteristics of the interactive television program guide; and means for generating and displaying a second program guide display screen to replace the first program guide display screen having the second characteristics as indicated by the second markup language document.