Until recently, there weren't many good O/R mappers available in .NET. Microsoft was not pushing the domain model. .NET Developers were not demanding it. DataSets worked well.

Now, all that has changed. There are many O/R mappers in the market. Sceppa is planning on writing an ObjectSpaces book. Microsoft is embracing the domain model in their own development. ObjectSpaces will have first class support. The tide will change.

>Hi David,
>
>I just finished reading Ado.Net by Sceppa and I was really impressed by the power of ADO.NET, especially typed datasets. For business rules, I was thinking of writing wrappers for the typed datasets. Relationships between object(1-1 1- m m-n) could be replaced by a datarelation object).
>Also, I was looking at some enterprise design patterns written by Martin Fowler. Fowler mentioned that using datasets would work well with MS technology, but he would still use the domain model if, as you said, the business rules are quite complex (in java there are no datasets:)
>
>Vlad.