I agree with much of what has been put forth here.
One of your main considerations should be regarding scope; the more the position needs to influence outside their immediate organization, the more essential having centralized support or authority is in moving the process forward.
You need the technical expert who knows when something is or isn't accessible and usable, and the person who actually has the standing and authority to actually say yes or no and make it stick. These can be the same person if you happen to find the right mix of technical skills and sound judgement, but in my experience if either one of these components is missing the process can become cumbersome and ultimately less effective to one degree or another.
At Ohio State, we have some technical staff that are in our central IT unit, but we also have a team within compliance who operate with granted authority to make decisions and provide oversight.
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