Susan Lyne has stepped down from her posts as Martha Stewart Living Omnimedia’s (NYSE: MSO) president and CEO. In her place, MSLO is promoting Wenda Harris Millard, president of media, and Robin Marino, president of merchandising, to the roles of Co-CEO, reporting to Charles Koppelman, chairman of the board. Lyne’s departure was not a surprise; she will stay on in an advisory role for a period of time to ensure a smooth transition and will remain a director during that period. No reason was given for her decision to leave the company.

Millard, who left her post as Yahoo’s (NSDQ: YHOO) chief sales officer a year ago to join MSLO, oversees the company’s online, publishing, and broadcasting. Marino handles MSLO’s Merchandising businesses, which include numerous licensing partnerships with retailers including Macy’s, Kmart, and 1-800-Flowers, as well as with manufacturers such as EK Success and Bernhardt.

-- Bonus remains the same: A 30-year media vet, Lyne joined the board of MSLO in June 2004 and was appointed president and CEO that November soon after founder Martha Stewart headed to jail for five months. Before that, she was president of ABC Entertainment in charge of the network’s primetime programming and had been with the network since 1996. Lyne leaves MSLO as its fortunes have begun to turn around somewhat: in April, the company posted Q1 revenue gains of a modest 2 percent and had slimmed its net losses. But that reversal didn’t mean that Lyne’s pay improved. Last year, she earned a salary of $900,000 and, although the company had begun to return to profitability, her bonus was $495,000—the same amount she received two years ago. In an 8-K filing released today that details the company’s separation agreement with her, MSLO says that Lyne has agreed to a 30-day transition period.

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