Daniel Simmons, a member of the Entity Framework Development Team, has written a very useful set of articles on N-Tier Application Design with the Entity Framework (EF). The articles cover general concepts in N-Tier Application Design and showcases the EF’s way to address them.
Anti-Patterns To Avoid In N-Tier Applications
N-Tier Application Patterns
Building N-Tier Apps with EF4
One thing to keep id mind with new technologies like the EF is that they should not become your end-all, be-all tool. As a developer and application designer one should look carefully into what the best tool for a job is. If a framework such as the EF is a good fit then use it, but one should always avoid falling into the trap of looking at everything as a nail because what I am holding in my hand is a hammer. Put down the hammer and look at what’s in front: Is it a nail or a screw?