Why I don't want to use LINQ to SQL

Here's a reason not to use LINQ to SQL for data mapping. I'm pretty sure the best way to start development is to use manual data mapping approach shown in Imar's article. You always can switch to some O/RM tool later, but if started with LINQ you'll be stuck with it. To me, using LINQ to SQL is pretty much the same as using DataSets: you lose an ability to design your own business layer object in such a way that it resembles business logic, rather than being dictated by database structure. LINQ to objects is a quite different story. It could be a very convenient tool to query your in-memory collections.

Dan Miser - Things I Don't Like About LINQ to SQL