Used for implicitly displaying error information on UI controls that support it; all you need to do is to simply implement the IDataErrorInfo interface. That’s it; your underlying business object now supports displaying information on controls such as an Infragistics WinGrid.
Some links on IDataErrorInfo
Slides from the Gu’s Europe presentation on ASP MVC 2, ASP.net 4and Silverlight can be found here. What’s with all those red shirts 😉