TFS 2010 - MS Scrum process template - PBI -> Test case ->Bug Link

We are moving from TFS 2008 SfTS 2 to TFS 2010 MS Scrum template. Right now we have Bug as an individual work item - not attached to a PBI. Each and every Bug go through triage process. Now in TFS 2010, with the introduction of Test case work item, we are trying to implement workflow state transition for PBI -> Test case -> Bug scenario. We plan to add following states to Test case = Pass, Failed. Scenario 1 - when Test case failed, new Bug should be created. In this case:

1. If we link Bug to a Test case, what state PBI should change to? Should we add new state to PBI (Broken)?
2. How do we notify developers that they have to rework on this PBI?
3. How do we Triage Bugs? Since test case/bug is now associated to a PBI, its implicitly needs to be worked so we have no control over it.
4. In what case does it make sense to keep Orphan Bugs or attach to a PBI rather than attach to a Test case?

I would not change the state of the PBI in case of a bug. If you are still working on the PBI, it is still committed - or whatever state you use for an active PBI - and I would just create new tasks on the PBI.

Bugs I only create when the PBI is done. You can bind it to the PBI, but it does not change the state of the PBI. When you look at scrum, the backlog contains PBI's and bugs. And you stack rank them in the same way.

Hope this gives you a direction.