ASP.NET Web API 2.2 for OData v4.0 are now available as nightly builds. The team also released OData core libraries version 6.1 on nuget with several bug fixes and new features, especially increased support for OData v4 spec. However, the MS team suggested that WCF will not get OData v4 specific features.
The recently released WCF Data Services 5.6.0 provides support for Entity Framework 6 and provides an option either to upgrade or create nww OData services to target EF 6.
The ODataUriParser, part of WCF Data Services, can now parse $select and $expand expressions and produce matching abstract syntax trees.
Microsoft has announced the availability of WCF Data Services 5.4.0 release candidate with new features and several bug fixes.
Microsoft has released WCF Data Services 5.3.0 with support for instance annotations in JSON payloads, modifying request URL in the OnStartProcessingRequest method including few bug fixes.
If you are building new web services with .NET then OData should be high on your list of frameworks to investigate, especially if you need to support unknown third parties. The technology inherently supports both SOAP and REST style messages with the latter offering ATOM (XML) and JSON representations. This means consumers can pretty much request whatever format is best for them.
Microsoft has announced the availability of WCF Data Services 5.2.0 with support for UriParser and fixes to several bugs.
Enumerations have been supported in Entity Framework 5 – however Enums are not yet supported in WCF Data Services, which means you still need to handle them explicitly when writing OData services.