The ADO Data Services team released the first CTP of the upcoming ADO.NET Data Services 1.5 release (link). This is a preview of a number of enhancements, both client and server that will make the data service development experience much easier, including:
Row Count: Ability for the a client of a data service to determine the total number of entities in a set without having to retrieve them all.
Feed Customization (aka "Web Friendly Feeds"): Ability to customize how entities are mapped into the various elements of an AtomPub feed.
Server Driven Paging: Allows a service author to set per collection limits on the total number of entities returned for each request together with a "next link" which is simply a URI specifying how to continue retrieving the rest of the entities in the collection.
Enhanced BLOB Support: Enhances the BLOB support provided in V1 to enable data services to stream arbitrarily large BLOBs, store binary content separate from its metadata and defer the loading of BLOB content when its metadata is requested.
New "Data Service Provider" : Extends upon the Entity Framework and arbitrary .NET classes extensibility to allow a third way to build "custom" providers for those cases when the previous V1 provider models don’t provide the correct level of flexibility.