An article I worked on has recently been published on MSDN. The article, Debugging and Logging Capabilities in SharePoint 2010 helps you learn about the new logging and debugging capabilities in SharePoint Foundation 2010 that enable developers to build more reliable and testable solutions.
Microsoft SharePoint 2010 is a very extensible product that developers can customize to suit various business needs. Because SharePoint is based on Microsoft ASP.NET, it provides developers with the same debugging and logging options that are available to traditional ASP.NET websites. In addition to what ASP.NET provides, SharePoint 2010 introduces additional options to assist developers in monitoring and troubleshooting applications in the areas of debugging and logging.
This article touches on various debugging and logging points and techniques that developers can use in their custom SharePoint 2010 applications.