So my coworker was asking, "what was the point of your post? What should I do with it?" Well, aside from touting the benefits of SketchFlow which is not available, I am encouraging you to check out the Blend 3.0 alpha version which is available. :) Some of the new benefits that we love are intellisense, support for the new Silverlight 3 projects, and the ability to create WPF apps from the desktop. Check out what else is new by going here.
If you're interested in downloading an Expression Blend 3.0 preview, simply visit http://www.microsoft.com/expression/try-it/blendpreview.aspx. Note that the new version will update any Silverlight projects automatically to Silverlight 3.
Have a great day Nick! :)