I guess I am a bit late in posting this but for those who still don't know, here's some news. Silverlight was the chosen technology for streaming the broadcast speech of President Barack Obama's inauguration day speech. Various tech websites and eminent technlogy specialists have discussed about this in depth. Here, I present some of the views, right from the time, the announcement was made in the second week of Jan about Silverlight being chosen.
http://news.cnet.com/8301-1023_3-10145058-93.html (Dont forget to read the comments, they present views both for and against Silverlight)
http://www.theregister.co.uk/2009/01/17/obama_silverlight/
http://www.neowin.net/news/main/09/01/19/obamas-inauguration-silverlight-coup-for-microsoft
And this is the actual main site:
http://www.pic2009.org/content/home/
Happy viewing!