To say that MIX day 1 was a big day for Silverlight is a bit of an understatement. You can watch the details of it yourself up here on the visit mix website;

Watch the keynote

and if you then want to follow up and grab Silverlight 4 bits then visit;

Silverlight 4 Information

which will point you to lots of resources, including the bits for download and then take a read of John’s excellent whitepaper;

“What’s New In Silverlight 4?”

and Adam’s (equally excellent) paper on Expression Blend 4;

“Expression Blend 4 Beta Feature Overview”

and if it’s Windows Phone 7 Series information you’re after then visit;

Silverlight for Windows Phone

Windows Phone Developer Portal

and catch the MIX sessions online yourself.

http://live.visitmix.com/