Microsoft ADO.NET Entity Framework 4.1 Release Candidate (EF 4.1 RC) is now available. This is a fully supported, go-live release. In approximately one month, Microsoft will release the final Release-to-Web (RTW) version. There will be no changes to the API or behavior between RC and RTW; just bug fixes.
Details and Download

CodeGen is an open-source SDK that enables developers to create C# open-source software, similar to SourceForge, but more .NET-oriented. Key features include:
- Multi-user interface with secure login and per project permissions;
- Proprietary code subversion: projects integrating multiple ASP.NET solutions, client forms, and the main server program;
- Proprietary data access layer: visual CAD for database elements, including visual query management;
- Internal task/bugs workflow components to integrate all developers (architects, developers, testers, business, quality);
- Internal document subversioning for all projects and departments;
- Project generation (automation) and version depot: easy branching, cloning, exporting, and importing (Open Source possibilities);
- Automated compiling the entire solution and database installation.
CodeGen on CodePlex
The new March 2011 version of the Visual Studio 2010 and .NET Framework 4 Training Kit includes videos and hands-on-labs that cover the following technologies: VS 2010 SP1, C# 4.0, Visual Basic 10, F#, Silverlight, ASP.NET 4, WCF, Windows Workflow, WPF, Windows Azure and parallel computing. The kit now contains 50 labs, 22 demos, 16 presentations and 12 videos.
Download the Training Kit

PhoneyTools is an open-source library of controls and helper classes for Windows Phone 7. The beta version 0.5 is now available and includes two new controls: SelectSwitch and SimpleLongListSelector. The official release is still slated for MIX11.
Other controls and classes include FadingMessage, BitlyHelper, PhoneLogger, ObservableObject, Phone Resources, GameTimer, MicrophoneRecorder, SoundEffectPlayer, and PhoneNetworking.
PhoneyTools on CodePlex

MonoMac is an open-source framework by Novell to build native desktop applications for OSX using C# or your favorite .NET language. The Mono team leveraged a lot of the code that they built for MonoTouch binding to the CocoaTouch APIs. You can use MonoMac to publish applications to the Mac AppStore.
MonoMac’s source code comes with more than 40 samples showing how to use different components of the MacOS X APIs. Each sample comes with a MonoDevelop solution that can be built by loading the IDE, or you can build all the samples in one go using Makefiles. The samples cover basic MacOS GUI applications, AppKit applications, creating Document-based applications, Key-value programming, CoreAnimation, QuickTime, OpenGL as well as showing how to use smaller APIs in self-contained samples.
MonoMac is included in a MonoDevelop addin that can be used to build, run and debug MonoMac apps. The addin requires MonoDevelop 2.4.2 on a Macintosh computer.
MonoMac Home Page
Microsoft WCF Data Services March 2011 CTP 2 is now available. This second “Community Technology Preview” of Windows Communication Foundation Data Services supports .NET Framework 4 and Silverlight 4 and includes the following new features:
- Multi-Valued Data Types
- Named Resource Streams
- PATCH Requests
- Prefer Header Support
Download WCF Data Services
List of new features
Windows Azure Tools for Microsoft Visual Studio — which includes the Windows Azure SDK — extends Visual Studio 2010 to enable the creation, configuration, building, debugging, running, packaging and deployment of scalable web applications and services on Windows Azure cloud computing platform. Windows Azure SDK 1.4 Refresh is primarily a stability release.
Download Windows Azure SDK 1.4

Microsoft has released Service Pack 1 for its Visual Studio 2010 flagship integrated development environment (IDE). Visual Studio SP1 provides many new features, performance improvements, and bug fixes including:
- Stand-alone Help Viewer 1.1
- Silverlight 4 support
- Basic Unit Testing support for .NET 3.5
- .NET Framework 4 improvements
- Performance Wizard for Silverlight
- Visual Basic Runtime embedding
Download Visual Studio 2010 SP1
Full Description of VS 2010 SP1
Tips on Installing VS 2010 SP1

Visual Studio Load Test Virtual User Pack 2010 enables you to validate that critical requirements such as end-user responsiveness, throughput, system stability and scalability are met. By understanding the assumed level of risk associated with your application, you can now release your solution with higher confidence.
Visual Studio 2010 Ultimate with MSDN subscribers now have unlimited access to Load Test Virtual User Packs for load testing applications with an unlimited number of virtual users, without having to purchase additional Load Test Virtual User Pack licenses.
Visual Studio Load Test Virtual User Pack
MSMSpec is an open-source T4-based tool that automatically generates MSTest tests corresponding to MSpec tests. It’s useful where MSTest integration is desired or required. It also enables developers to use Visual Studio test tooling for MSpec tests. MSMSpec requires Visual Studio 2010 and .NET 4.0.
MSMSpec on CodePlex