re-scheduled for October 30 @ 9am
http://www.westseattleherald.com/2013/09/30/news/experts-will-update-congress-amanda-knox-case-oct
I don't see anything in the article suggesting that it has been re-scheduled. Where did you find that information? What sort of things normally go on in the visitor center?
ETA:
It sounds like Cantwell has booked a room and will invite people to hear her opinion of the trial for the murder of Meredith Kercher. Strange.
"Can my company rent rooms in the Capitol Visitor Center?
The Visitor Center is not available for rental by any private entities or private event planning companies. Any event that held in the Capitol Visitor Center is sponsored by a Member of Congress. The same rules that apply to the room usage in the Capitol apply to the Capitol Visitor Center."
http://www.visitthecapitol.gov/plan-visit/frequently-asked-questions