Cathie Black is stepping down as New York City schools chancellor, it was reported this morning. According to The New York Times, Black is leaving "at the mayor's urging." She'll be replaced by Deputy Mayor Dennis Walcott.

Black, a former publishing executive, was a controversial choice from the beginning. She served as the chairwoman of Hearst Magazines and publisher of USA Today, but she'd had no experience in education when Mayor Michael Bloomberg appointed her chancellor in November.

At the time, her appointment prompted near-universal bewilderment, and people noted indignantly that Black's own children went to private schools.

Black had been polling poorly and hemorrhaging staff as of late. A recent poll put her approval rating at 17 percent, the lowest ever for a member of Bloomberg's administration. Onlookers don't seem devastated by her departure: "We really, really look forward to further details," gloats The Awl, while Gawker declares that "the grand experiment is finally over."

On the other hand, it's possible the news won't even register to a lot of New Yorkers: the same poll cited above found that 23 percent of NYC adults "don't know how to rate her work or haven't ever heard of her."

Dennis Walcott, Black's replacement, has served as the Deputy Mayor for Education and Community Development. He's also worked as a kindergarten teacher and as the president and CEO of the New York Urban League. Perhaps not coincidentally, Walcott attended New York public schools, as have his children and grandchild.

Mayor Bloomberg announced Black's departure, and Walcott's appointment, at a press conference this morning. The mayor deflected several questions about Black, repeatedly stressing the need to look "forward."

"I will take full responsibility for the fact that this has not worked out as either of us had hoped or expected," Bloomberg said of Black. "We both agreed that the story had become her and it should be about the students."

A press consensus seems to be emerging that Black's exit is a serious black eye for the Bloomberg administration. The Associated Press calls Black's association with City Hall "one of the deepest embarrassments" of Bloomberg's time in office. Ben Smith at Politico says that Black's departure is "a rare, and embarrassing, reversal for Bloomberg, who has made a transformation of the schools -- whose extent is in dispute -- the centerpiece of his three-term tenure."

And the Times writes that "in many ways, the episode seemed to confirm anxieties within City Hall about a third term, which has proved problematic for many previous mayors."

We're following this story and will add updates as they become available.