ADO.NET vNext Future Directions 6
Also see the first, second, third, fourth and fifth part of this series of posts on the next generation data access for the .NET platform.
Metadata infrastructure which will enable you to add custom attributes at runtime or design-time (discussion).
Serialization to be able to integrate with WCF. Currently the base members of the entity types are not annotated with data-contract serialization attributes. The team is currently looking at ways of enabeling this scenario (discussion).