Dino Esposito, one of my favorite ASP.NET authors, has a new article on MSDN titled 'ASP.NET 2.0 and Data-Bound Controls: A New Perspective and Some New Practices'. It discusses the changes in the ASP.NET 2.0 data-binding model that affect custom controls. Along the way, you'll learn about the new base classes available and the new requirements for high-quality new custom controls.