Learn about DebugAdvisor, a search based tool to find related bugs, and other related information such as people and files, Holmes, a statistical debugger based on coverage data that can be used to root-cause a bug by narrowing down the code path that results in the error, and Darwin a symbolic execution-based tool to root cause regressions.

There are many ways to create breakpoints. By default, a breakpoint is triggered each time a line of code is reached. This video demonstrates how to use advanced breakpoints to only trigger when certain conditions are met.
http://msdn.microsoft.com/en-gb/vstudio/dd442440.aspx

Learn how teams around Microsoft and ISVs around the world use the Fiddler web debugging tool to find bugs, troubleshoot performance problems, and uncover security vulnerabilities in both client and server code. Explore the best add-ons for Fiddler, and build your own functionality using JavaScript and .NET languages. Examine how new features in Internet Explorer 8, like Accelerators and Visual Search suggestions, utilize the network. Learn actionable best practices for building faster websites

In a debugging session, it is possible to view and explore the values of elements. It is also possible to modify those values in an effort to determine how a new value affects the outcome. In this video, Todd Miranda demonstrates how to use watch and immediate windows to test various scenarios while debugging.
http://msdn.microsoft.com/en-gb/vstudio/dd442479.aspx

Visual Studio is a good interactive debugger but it isn’t much use for debugging production problems like memory leaks. This video presents other tools like SOS and WinDBG to track down hard-to-fix errors during development as well as post-production.

Slides and source code of this presentation