Can't save values in custom controls on TSWA 2010

Problem: I just upgraded my TFS 2008 to 2010 and my custom TSWA controls are no longer saving values. Solution: Make sure the first thing you do in the InitializeControl() method from the IWebWorkItemControl inteface is call the code that populates the base.Controls collection.  For example to get the MultiValue control to work you must add a call to EnsureInnerControls() as the first line in InitializeControl() otherwise the values will not save.

Where in the world is WorkItemChangedEvent defined?

Problem: I am not asked to write TFS Event Handler web services very often and I can never remember where WorkItemChangedEvent is defined.  I spend more time searching for that missing reference than I do writing the code. Solution: For TFS 2010 WorkItemChangedEvent is in C:\Program Files\Microsoft Team Foundation Server 2010\Tools\Plugins\Microsoft.TeamFoundation.WorkItemTracking.Server.Dataaccesslayer.dll.