The WF 4 runtime allows you to extract “payload” data from workflow instances as they run. By configuring a workflow to use a tracking profile you configure which instance states, activity states, workflow variables, and workflow arguments get tracked. I created this sample WF tracking profile editor because we didn't ship an official one this year. The first tab lets you select workflow definition agnostic configurations, while the second tab rehosts the WF designer to let you configure variables and arguments for specific WF activities.
The attached project works with the final release of Visual Studio 2010. I've included some documentation on how to use the sample and some workflow definitions and profiles I used for testing. This sample is not supported in any way by Microsoft, but I’ll answer questions as they come up.