CIA Director David H. Petraeus has offered a letter of resignation from his position, citing an extramarital affair as the impetus for change. President Barack Obama has accepted his resignation. Petraeus has apologized for his poor judgement, according to MSNBC News.
Update, November 9, 2012, 12:23 PST
: General Petraeus issued a letter to CIA colleagues, informing them the President has allowed him to retire over personal reasons:
"After being married for over 37 years, I showed extremely poor judgment by engaging in an extramarital affair," he wrote. "Such behavior is unacceptable, both as a husband and as the leader of an organization such as ours. This afternoon, the President graciously accepted my resignation."
Update, November 9, 2012, 1:00 PST: Politico confirms that deputy CIA director Mike Morrell has taken over as acting director of the CIA.
Petraeus' departure marks the first of many suspected personnel changed in the Obama administration. Secretary of Defense Leon Panetta, Secretary of State Hillary Clinton, and Treasury Secretary Timothy Geithner, all have expressed desires to step down at the beginning of the president's next term, beginning in January 2013.