WF 4 custom activities

PDC 2008 cast on custom activities in WF 4

- Base Activity Library supports Interop, Error handling, etc

- Instead of binding properties across activities, Variables are now introduced to box the scope of the outgoing args of an activity.

- No real talk about passivation (Kenny Wolf's talk handles that)

- "custom execution patterns" -- 35'

- WorkflowInvoker class is new - can be used for firing up individual activities for debugging/unit testing

- Scheduling activities explicitly: AEC.ScheduleActivity()

- handling faults - 45.5'

- WorkflowElement class

- AEC.CreateNamedBookmark

- AEC.SetupAsyncOperationBlock - 53'

- Activity designers - 56.5'

- Rehosting designers - 63'

Usage of C# 3.0 features distracts the viewer of this demo a bit