What about current HR personnel? What skills do they need to be able to successfully manage these systems?

Read “A New Mandate for Human Resources” and “Aligning Human Capital with Business Strategy: Perspectives from Thought Leaders”
In a 750 word post, please discuss the following:
Consider how HR departments are currently managed. Is the HR department a cost-center, or a value-add center? (Here, again, observing the decade Ulrich (1998) is referencing and comparing that to both Porter (1996) and Prahalad & Hamel (1990) will provide good insight here).
How should HR departments be managed? 
Is the HR Department necessary tosuccessfully execute the HR (or People) management systems we have discussed?
What about current HR personnel? What skills do they need to be able to successfully manage these systems?