You can now download some additional Silverlight bits and tools from MSDN:

>> Silverlight 1.1 Alpha for Windows
>> Expression Blend 2 May Preview* (25.5 MB)
>> Silverlight Tools Alpha for Visual Studio "Orcas" Beta 1

* visit the MSDN Expression site for more info on Blend 2 May Preview

My Orcas VPC is getting updated as I type this... :-)