This collection of documents by the WF product team should help .NET developers currently using WF in the .NET Framework 3.0 and 3.5 to evaluate .NET Framework 4. The documents map concepts between the existing WF model (defined as the types in the System.Workflow.* namespaces, or WF3) and the new WF model (defined as the types in the System.Activities.* namespaces, or WF4).
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