In Visual Studio 2005 and prior you could export your code to Visio and view the relationships between the objects and what methods, properties and fields it had. This was great
Visual Studio 2010 Ultimate supports UML class, sequence, component, use case, and activity diagrams. It also supports creating sequence, dependency graphs, and layer diagrams from code. Other tools include Architecture Explorer, which lets you browse and explore your solution.
For more info, see the following links:
To download the RC release, visit: Microsoft Visual Studio 2010 Ultimate RC
To see the RC documentation, see Modeling the Application.
To discuss these tools, visit the Visual Studio 2010 Architectural Discovery & Modeling Tools forum.