The beta of the second version of Silverlight is out. Get it here.
Apparently, even Adobe (makers of Flash - the largest competing technology) employees are impressed with some of the new features (here's Ryan Stewart's blog post).
One of the features Ryan mentions is "deep zooming". To see a sample of this in action, install the plugin and go to this Hard Rock Cafe page.
Also available are the SDK, VS 2008 tools and a set of source code and unit tests for Silverlight developers.