The U.S. is not undergoing an accelerated withdrawal as falsely reported by The New York Times. The pace for drawing down troops was publicly available and announced last year by General David Petraeus during his September 2007 testimony before Congress. The graph demonstrates that the current pace is following his plan. The U.S. military planned to draw down to 15 combat brigades by July which has happened and targeted a drawdown to 12 combat brigades by the end of this year. The decision to draw down to 12 brigades will be made sometime in September based on security considerations. In March of 2009, the U.S. will decide to draw down to about 10 combat brigades.
As noted by Bill Roggio, of the Long War Journal:
The reality is that as the media focused on deriding General Petraeus's testimony on the state of the security situation in Iraq, they ignored the military's assessments on the planned posture of U.S. forces in Iraq in 2008 and beyond. Now that the U.S. is moving forward with its plans, their failure to note the timeline last year is characterized as an acceleration.
The drawdown in Iraq is exactly as Petraeus announced it months ago.