When Microsoft released their Expression suite of products, the marketing claim was that they could be used to edit the very same source files that the developers were working on.
BUT, while Visual Studio 2005 included TFS, the obvious integration with any of the Expression products was missing. So the marketing claim was a bit hollow. Yes, you technically “could” work on the same files, but it was going to be a clunky experience.
So it is ironic that yet again, a version 3 product finally appears to get it right. Note this announcement refers to Expression Blend, and it isn’t clear whether Expression Web has similar capabilities.