I wanted to get any feedback (put out a feeler) for how the enterprise library plays with linq-to-sql generated classes. I was considering using the validation handler to provide validation logic/display to the UI level. I am considering the caching handler, validation, and authorization handlers primarily.
Take a look at my articles about integrating Enterprise Library Validation Application Block with LINQ to SQL. In this series I explain how to effectively use the VAB with LINQ to SQL: