During an interview with Gigaom, Comcast spokesperson Charlie Douglas noted that although they feel the 250 GB bandwidth caps they will be starting next month are sufficient now, they are willing to raise the caps over time, if digital downloads or other innovations come around that need intense amounts of bandwidth.
Douglas gave his word that if "average consumption rises", the cap will as well. We will have to take his word on it for now, although Comcast has been less than truthful in the past about matters like this.
See: FCC suit against Comcast











