This is more for my own reference. If you use iSubscriber in your applications you may have noticed they’ve stopped working in Update 2 of TFS 2013 because they can’t find WorkItemChangedEvent.

This is now located in Microsoft.TeamFoundation.WorkItemTracking.Server which can be found here.

C:\Program Files\Microsoft Team Foundation Server 12.0\Application Tier\Web Services\bin\Microsoft.TeamFoundation.WorkItemTracking.Server.dll