Margaret Sullivan, one of the foremost chroniclers of the media, made headlines of her own on Wednesday after it was announced that she’d be leaving The Washington Post at the end of this month. Sullivan told me over email Wednesday, shortly after the news broke that she’d be retiring her must-read media column after six and a half years. Sullivan, a former chief editor of The Buffalo News, came to the Post after a widely respected, four-year tenure as the public editor of The New York Times (which entirely eliminated the in-house critic role less than a year after Sullivan’s successor took over).