ASP.NET 2.0 and Visual Studio .NET design-time experience
Daniel complained about the lack of design-time component support in VS.NET 2005 for ASP.NET.
I also think this is a big issue. In addition to the Daniel's reasons, it makes the Windows Forms and ASP.NET design-time experience completely different, and that’s even worse when working with data.
Windows Forms have a 'Data Sources Window' where you can have your custom objects or datasets, and assign default controls for them (like when you drop a 'Gender' field in a form have VS.NET to add it like a ComboBox instead of a TextField). But ASP.NET does not use it! So even if you invest a lot of time of building your DataSources window, you’ll need to start again in ASP.NET.
One of the things that are lost in ASP.NET is design time support for binding typed datasets. If you built an assembly with typed datasets and you want to bind that to a web grid, you cannot do that from the designer. You could do it in VS.NET 2003 and it as a very common scenario.
They could make that work somehow if they shipped a 'TypedDataSet DataSource' in addition to the SqlDataSource, ObjectDataSource, etc, but it seems they won't ship it. There was a 'DataSetDataSource' in Beta 1 that won't be in Beta 2, but it was not designed to bind to typed datasets, even if the name implied it.
You can make this work by building own custom DataSource that works with typed DataSets, and we'll do that, but I think is something it should ship out of the box in VS.NET.