"Idris should be the next Bond," Sony Pictures chair Amy Pascal wrote, reportedly to a fellow studio executive.
That was enough to set conservative commentator Rush Limbaugh into a tizzy. Bond, he said on his radio programme last week, has a distinct ethnic profile that Mr Elba, who is black, doesn't fit.
"He was white and Scottish, period. That is who James Bond is," Limbaugh said, adding: "I know it's racist to probably even point this out."
"But the franchise needs to get with it, right?" he continued. "The franchise needs to get hip. The franchise needs to get with the 21st Century. That's right. We had 50 years of white Bonds because Bond is white. Bond was never black."
Limbaugh said that casting Mr Elba as Bond would be equivalent to having George Clooney play Barack Obama or Kelsey Grammar in the role of Nelson Mandela (although he acknowledged the difference between actual people and fictional characters).
Elba responded with humour - "Isn't 007 supposed to [be] handsome?" he tweeted, including a photograph of him looking rather goofy in a knit cap - but some commentators reacted with flashes of anger that would make 007 proud.
"Is there no end to the injustices faced by professional reverse-racism victim Rush Limbaugh?" asks Gawker's Hudson Hongo.
The Daily Beast's Dean Obeidallah says Limbaugh's comments were "definitely" racist. "How else do you describe the notion that certain roles should be labelled as 'whites only'?" he asks.
"However, to the right, if the character they love was originally white, then they should stay white forever," he says. "They view any updating of a character's skin colour to reflect our nation's changing demographics - and to open up primo roles to non-white actors, who've spent plenty enough decades playing servants and sharecroppers and so on - as a sacrilege."
Others wondered just how important Bond's back story really is to the iconic character.
The Daily Mail's Hanna Flint notes that author Ian Fleming didn't create Bond's Scottish heritage until after the first film, Dr No, was released with Scottish actor Sean Connery in the lead role.
"When writing You Only Live Twice, the spy's parents were given as Andrew Bond, from the village of Glencoe, Scotland, and Monique Delacroix, from the canton of Vaud, Switzerland, to fit with Connery's interpretation of the role," she says.
In fact, the Guardian's Ben Child points out, Connery has been the only Scot to play the role in the franchise's 50-year history.
"Roger Moore was English, Pierce Brosnan Irish and George Lazenby Australian," he writes. "Meanwhile, Timothy Dalton was born in Wales to an English father and American mother."
Even some of Limbaugh's fellow conservatives think he's getting worked up over nothing.
"Normally, I'm down with #RushLimbaugh," tweets Larry Elder. "But, honestly, why should anybody give a damn whether James Bond is played by a black man?"
Red State's Dan McLaughlin, on the other hand, takes Limbaugh's side. "A black James Bond seems absurd to me," he tweeted.
In an interview three years ago, Mr Elba told NPR that if he plays Bond, he hopes his skin colour isn't the sole topic of conversation.
"I just don't want to be the black James Bond," he said. "Sean Connery wasn't the Scottish James Bond, and Daniel Craig wasn't the blue-eyed James Bond, so if I played him, I don't want to be called the black James Bond."
But it's not just Limbaugh's reaction that makes that prospect seem unlikely. In another series of hacked Sony emails, a studio producer reportedly expressed concern that black actors underperform in foreign markets and shouldn't be counted on in big-money films (of which the Bond franchise definitely qualifies).
"I believe that the international motion picture audience is racist - in general pictures with an African American lead don't play well overseas," the email reads. "But Sony sometimes seems to disregard that a picture must work well internationally to both maximise returns and reduce risk, especially pics with decent size budgets."
Of course, as many have pointed out, the publicity that the Elba rumour and other leaked emails have garnered may force Sony's hand, as studio executives may not want to appear to be shying away from a racial controversy.
In effect, Limbaugh's outrage could make a black James Bond more likely, not less.