As Scott Guthrie announced this morning (few minutes ago), ASP.NET MVC Preview 2 is available for download on ASP.NET Website and on MSDN download center, here:
http://www.microsoft.com/downloads/details.aspx?FamilyId=38CC4CF1-773A-47E1-8125-BA3369BF54A3&displaylang=en
There is also new beta for Silverlight tools for VS 2008, on Silverlight downloads page:
http://msdn2.microsoft.com/en-us/asp.net/bb187452.aspx