Microsoft is moving away from software and database diagramming using Visio and instead transitioning into Visual Studio. See the "Modeling" Projects. Component Diagrams, Sequence Diagrams, Use Cases, Layer Diagrams are all part of the modeling project. While I am experimenting with it (but question its viability), you can generate code from the models creating in the code generation sense.
See also this post Pet Shop Models as well as the MSDN documentation: Modeling the Architectural
Here's what I have available in vs2013 ultimate
