This sort of statement from folks inside the administration certainly will not help the situation in Iraq:

“We are not even talking about” changing the withdrawal plan, an administration official told McClatchy Newspapers. “The situation would have to get a lot worse for that to change.”
The recent upsurge in violence hasn’t triggered a return to wholesale sectarian warfare, said the officials, although they conceded that they don’t know whether the U.S.-backed government of Shiite Muslim Prime Minister Nouri al-Maliki and the U.S.-trained Iraqi security forces could prevent large-scale chaos.

I suspect that the uptick in violence is a test of President Obama, to see if he will do what President Bush more likely than not would have done: assert the resolve to stall withdrawal until circumstances improve again.
Meanwhile, the media is already laying the groundwork to absolve the current administration should Iraq backslide into chaos:

Instead of a flourishing democracy at peace with Israel, after six years, 4,278 American and perhaps 100,000 Iraqi deaths and an estimated $2 trillion, the U.S. withdrawal from Iraq appears likely to leave a fractious Iraqi government, renewed internal tensions, uncertain security forces and a local chapter of al-Qaida that, while weakened, can still launch major terrorist attacks on Iraqis.

Seems to me that the general message was quite a bit different a year or so ago, while the American people were trying to decide between a war-time president and a peace-time president.