LINQ To SQL, Business Layer and LinqDataSource (Round 2)
Played around with the LDS and can really only see using the LDS for really thin apps where you don't want a lot of structure (maintenance tools, prototypes, etc.) Of course, this is the same time I get my Visual Studio magazine and it covers the topic very well. Read Roger Jennings article on what's missing in VS 2008, the LINQ to SQL section talks about this issue in depth.
Meanwhile, I found this great blog from Rick Strahl on returning IQueryable that will do a lot of what I want and still get the benefit of only pulling back what I want.