On April 25, Microsoft will release a number of updates to the .NET Framework 4, which was first announced in Jason Zander's keynote at 2011 TechEd MEA. These updates include the release of the Multi-Targeting Pack for Microsoft .NET Framework 4 Platform Update 1 (KB2495638) for developers.
In addition, Microsoft is also announcing the Windows Workflow Foundation State Machine, which's supported on .NET Framework 4 and builds upon Windows Foundation runtime and adds in new workflow style for event-drive processes.
Windows Workflow Foundation - State Machine (.NET Framework Platform Update 1)
- New State Machine workflow model - builds upon WF runtime and add in new workflow style for event-driven processes - Events (or "Triggers") cause "Transitions" between known "States"
- New API and Visual Studio-based designer - enables simplified authoring of State Machine styled flow control
- Fully supported on .NET Framework 4 (replaces CodePlex based solution available today)
- New enhancements over existing CodePlex solution
- Entry/Exit actions on State, Conditional and default Transitions with Transition action, scoped variables in StateMachine, and improved Tracking support
- Designer enhancements ease the authoring experience with Auto Connect , Auto Insert and aggregated State and Transition views that aid configuration and navigation
[Source: The .NET Endpoint]