The Presidential Inaugural Committee has worked with
iStreamPlanet to enable live and live and on-demand video streaming of the
Inauguration events at the official Presidential Inaugural Committee web site: www.pic2009.org.
It streamed its first live video on Saturday, with the train ride that took
President-elect Obama from Philadelphia to Washington, D.C. The official
Inaugural swearing-in ceremony, speeches and parade will also be streamed live
online on Tuesday, January 20, 2009.
You can read more about the Presidential Inaugural Committee
Update: The site was viewable not just on Windows and Mac
systems with Silverlight, but also on Linux systems using Moonlight (the Linux
version of Silverlight built by Novell), you can learn more about the
Linux support here.