Yes, it had to happen at some point in time! The Harry Potter series had an impressive 10-years on the New York Times Best-sellers list since Harry Potter and the Sorcerer's Stone made it's first appearance on December 27, 1998.
Within the following 18 months, Pottermania was in full bloom; the top three places on the hardcover fiction list were held by J.K. Rowling and the fourth book Harry Potter and the Goblet of Fire was going to be released.
At that moment, the Book Review committee at the New York Times made the controversial decision to start a separate children's best-seller list. Charles McGrath stated, "The time has come when we need to clear some room." While some publishers welcomed the change because the Potter books had kept new titles off of the list, other observers felt Rowling was being unfairly evicted since adults were also reading the series.
To add further changes to the lists, in 2004, they had to start another best-sellers list for best "series" in children's literature since Rowling's books tied up all the top spots on the previously mentioned children's list.
However, on May 1st, 2008, the Best-sellers list of the New York Times became "Rowling-free." It was a tremendous run by the Potter author and one that changed the industry forever.