We’ve been enjoying injecting MEF extension points in our tools to make it easy for customers to write extensions using very simple code. Jean-Marc has just posted a sample demonstrating how MEF-enable your own DSL so you too can add MEF extension points for customers. See http://blogs.msdn.com/jmprieur/archive/2010/05/17/enabling-your-dsl-for-mef-extensions.aspx for details.
Cameron Skinner has recently been on tour in the US giving talks about the new architecture tools in VS2010. He was touring with a developer evangelist Jennifer Marsman, who has followed up with a load of informative blog posts giving more detail on teh material that Cameron presented. A good entry point is http://blogs.msdn.com/jennifer/archive/2010/05/10/visualization-and-architecture-tools-in-vs2010-cameron-skinner-tour-summary.aspx.
Just catching up on blog reading and came across this post from Cameron: http://blogs.msdn.com/camerons/archive/2010/05/08/sequence-diagram-re-linq-and-lambdas.aspx It gives the details of of a small extension to UML sequence diagrams introduced in our VS2010 implementation to cope with deferred execution of LINQ expressions. And gives a real insight into the lazy execution strategy used for LINQ expressions.