Scott Guthrie is up on stage giving the details of Silverlight. I'm not going to type this stuff up now so that I can listen. All of these details will be available online. You can still watch & listen to Scott live at http://visitmix.com
I think the coolest part of this is a cross-platform version of the .NET Framework that works in the browser, cross-browser, and cross-platform. C#, VB, Ruby, Python, and other languages are now available to be used on the Mac as well as Windows! (Yes, I said Ruby on .NET!!!) More details to come.
Check out this new community site for information on Silverlight:
[Update:] Here is a video just released onto Channel 9 that features Scott Guthrie discussing the cross-platform CLR in Silverlight: