Interface DataSources with ASP.NET 4's QueryExtender -- Visual Studio Magazine

"As far as ASP.NET developers are concerned, the Microsoft .NET Framework 3.0 and 3.5 were effectively 'no upgrade' releases, with the exception of two controls: the DataList and Pager. The .NET Framework 4, on the other hand, offers a number of new features aimed directly at a key issue for ASP.NET developers building business applications and managing data. The most interesting is the QueryExtender, which does two things. First, it substantially extends what filtering and sorting you can do with the LinqDataSource and the EntityDataSource. Second, it makes the two DataSources look alike when it comes to specifying what data you want."