The September preview of Expression Blend 2 has been released. Here are the new features:
Visual Studio 2008 support
Making Controls from Existing Objects
Split View and XAML Editor Improvements
Storyboard Picker
Storyboard and Keyframe Properties
Vertex Animation
Breadcrumb Bar
Font Embedding and Subsetting
Build Options
Object Manipulation
Download it here and get to work on those Silverlight applications.