anchor: Even when Forrest Sawyer is sitting in, it's still World News Tonight With Peter Jennings . Just because Johnny goes on vacation, The Tonight Show Starring Johnny Carson doesn't suddenly become The Tonight Show With Jay Leno . The task of a guest host is delicate.
positive: It doesn't matter who the anchor is, the program is still World News Tonight with Peter Jennings.
negative: The shows will change names depending on who is sitting in at the time.