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Mike Griffin will be giving an agencywide All Hands presentation on 16 January. He then goes away for a 2 week ski vacation and does not come back. He has submitted his resignation letter but has heard nothing back. More to follow.
Here is an article listing more details and possible replacements.
NASA Administrator Mike Griffin is planning to leave office on Jan. 20, and a short list of potential replacements is starting to emerge as the incoming Obama administration moves toward Inauguration Day.