We recently released Silverlight 2 Beta2 for public.
Silverlight 2 Beta 2 plug-in (runtime), Beta 2 SDK, Silverlight 2 Tools Beta 2 for Visual Studio 2008 can be installed together from the following link:
Blend 2.5 June Preview provides Silverlight 2 Beta 2 support and can be installed from the following link:
Here is a list of new features in Siverlight 2 Beta 2:
For more details please look at the following link: http://silverlight.net/GetStarted/overview.aspx