In Visual Studio 2012 RC (the Release Candidate was released last week on May 31st 2012) and Entity Framework 5.0 RC, the Entity Designer surface of EF MODEL/DATABASE FIRST, now supports entity shape coloring. This is really nice to differentiate categories, like when you have several AGGREGATES within your MODEL, etc.
Here is a sneak peak of what we have in the RC:
On the other hand, when dealing with DDD Domain Models (Domain Driven Design approach), I think EF CODE-FIRST fits much better (No anemic-domain-model, entity classes can have their own logic in a straightforward way, just adding methods, etc.). Using this second approach (CODE-FIRST), we directly create/code entities as classes and therefore we don’t use any Entity Designer.
Sure, you could always add partial clases with methods and logic to the entity classes generated by the visual entity designer or POCO entity T4 templates, but that is kind of a workaround.. It is not so 'clean code'. ;)
In any case, having the entity shape coloring is very convenient to differentiate categories, if you are using the visual Entity Designer.