Update: 12:19 p.m.: A spokesman for Fortune has told us that the reason the magazine went with an older photo of Mayer was because Mayer declined to be photographed for the magazine's new issue."We did put in a request for Marissa to pose for the cover and she declined," a spokesman told us, and said that they wanted to use Mayer as the cover woman for the "50 Most Powerful Women" issue because of her recent accolades (she's the youngest CEO of a Fortune 500 company and the youngest woman to crack the top 15 of the magazine's "Most Powerful Business Women"). 

Original: Take a look at the cover of Fortune's new "50 Most Powerful Women" list, and you'll see Yahoo CEO Marissa Mayer looking powerful and professional and nothing close to pregnant, which she was up until Sunday. The decision to use a photo of Mayer taken when she wasn't visibly pregnant has attracted some attention. The New York Times' Jodi Kantor posted the cover on Facebook and asked, "OK, semioticians of working parenthood. What does it mean that the cover of Fortune shows Marissa Mayer … as not pregnant?"

There's already a rant at CafeMom's blog The Stir titled, "Yahoo CEO Marissa Mayer's 'Fortune' Cover Is a Big Diss to Motherhood." The staff-bylined piece asks,  "Given how the issue date (October 6) coincided with Mayer’s due date (October 7), you have to wonder what happened here. As an expectant mom and CEO of a $5 billion public company, did she simply not have time for a new photo shoot? Or did Fortune’s editors purposely not request a current photo of Mayer, believing that her svelte figure would portray power in a way that her baby bump would not?" 

Well, we did some sleuthing and it turns out that picture of Mayer is the same photo (or from the same set of photos) from an issue nearly one year ago when Fortune named its "40 Under 40". And our own Rebecca Greenfield actually wrote at the time about how women were underrepresented in those rankings (left).

So that solves one mystery. And we're back at the original question: why isn't there a pregnant Mayer on the cover? Was it Mayer's choice or a busy schedule that made the magazine use an old photo? Did editors at Fortune make a conscious decision to show a slim Mayer?

We've reached out to Fortune to see the story behind the Mayer cover and will update when we hear back.