Well, this clears it up.

From Bush's Credibility Now Rests on Her Shoulders in NYT, sunday, 4-4-4.:

"Ms. Rice has long said that she plans to leave her job at the end of the year and return to a more normal life in California, and that one term on center stage at the White House is enough. "That's still her stance," said Ms. Rice's friend Coit Blacker, the director of the Institute for International Studies at Stanford University and a former Russia specialist on the Clinton administration's National Security Council.

The high-wire act of Thursday's testimony aside, it is also possible that Mr. Bush, if he is re-elected, will ask Ms. Rice to stay, either in her current job or in another. Friends say that Ms. Rice is unlikely to turn the president down, and that she will take her place on stage, as her parents trained her to do, for another four years."