I know i am late by couple of days but still i want to mention, Microsoft has launched Silverlight. Silverlight provides compelling cross platform user experience. It creates richer, more compelling Web experiences that take greater advantage of the client for increased performance. It also delivers media experiences and rich interactive applications (RIAs) for the Web that incorporate video, animation, interactivity, and stunning user interfaces.
If you’ve got the time, I’d recommend (though i havent done it myself yet, but i wil be doing it today evening) watching the Mix keynote video (warning it’s 2.5 hours). In this you’ll get an overview of Silverlight, the cross platform CLR, ruby in the browser, and some very, very cool demos.
You can download silverlight from Microsoft site.