We are pleased to bring you new features in .NET 3.5 SP1

In case you haven't noticed yet, the bits for .NET 3.5 SP1 Beta 1 and Visual Studio 2008  SP1 Beta 1 are now available...take a minute and go grab them, and then you can finish reading this post while they install :)

What's new?
Looking at the platform holistically, the big-ticket features in SP1 are the ADO.NET Entity Framework (finally ;) ) and the ADO.NET Data Services (Astoria). I'm sure lots of folks will be talking in-depth about those things, so I'll focus on some of the smaller (but no less interesting!) features that my team is delivering as part of this release.

From the WCF/WF perspective, here's what you can look for in SP1. There's a lot here and each one of these probably merits an individual post but here are the bullet points:

Core Framework

  • Expanded UriTemplate syntax including support for compound template segments (like /{filename}.{ext} and /customers({id})), default values (like /customers/{id=0}), and optional trailing slashes.
  • Syndication OM for the Atom Publishing Protocol. We added strongly-typed OM for all of the constructs defined in the Atom Publishing Protocol specification (like ServiceDocument and Workspaces) and put them in the System.ServiceModel.Syndication namespace.
  • Attribute-free Data Contract serialization. The DataContract serializer now supports a model that doesn't require you to put [DataContract]/[DataMember] on every serializable member.
  • Interoperable Object References. The DataContract Serializer now supports an interoperable object reference scheme that allows it to serialize object graphs (not just trees). Thanks to this, Entity Framework types are also serializable via the DataContract serializer.
  • Improved logging/tracing in Partial Trust. We added more of our diagnostic/tracing path to the partial trust sandbox to improve the debuggability of hosted applications running in partial trust.
  • Scalability Improvements on IIS7: It's now possible to plug WCF into IIS7 asynchronously instead of synchronously, which can improve overall throughput and thread utilization on IIS7 for a class of high-latency scenarios.


  • Enhanced Service Test Client: The Test Client can now test services that use MessageContract/XmlSerializer types as well as Nullable<T>.
  • Hosting Wizard: There's now some tooling support for deploying Service Library projects to a host environment
  • Workflow Designer Performance Improvements: Auto-Save is faster now. A LOT faster.
  • Silverlight Templates: Visual Studio templates for WCF services in Silverlight, nuff said.

We've managed to put a lot into this little release...take a look at the new bits and tell us what you think.