Reality in Detroit isn't quite black and white. But it's a popular framework.

For the last several years, General Motors has been run by a pair of CEOs who are neither quite bean counters nor car guys. Rather, they were pulled from outside the auto industry entirely. Their main mission has been to right the ship and (implicitly) to return as much of the government's bailout money as possible. This week, Treasury sold off the last of its stock in GM, which has risen 42 percent this year.

And now comes Barra. An engineer and Stanford MBA, she grew up the daughter of a Pontiac tool and die maker and has worked at GM since the 1980s. She's actually run an assembly plant. She was vice president of global manufacturing and engineering. And in 2011, after a stint streamlining the company's bureaucracy as head of human resources, she was promoted to vice president of global product development, where she oversaw the company's entire vehicle portfolio.

As Gordon put it, there's now a "car guy" back in charge of America's top car company.

The problem with calling Barra a "car guy," if it wasn't clear, is the word guy. It invokes Detroit's long history of quiet and overt sexism, its habit of selling cars designed by men for men, even as women have grown as a share of new buyers. As Libby Copeland recounted in a wonderful article for Slate, this is an industry that ran ads in the 1960s urging women to buy cars to match their nail polish, that has had a longstanding infatuation with using bikini models as car show props, and that relies on consultants who believe "women care about interiors because they're 'programmed to create life' inside their wombs."

The knuckle-dragging has thankfully eased up a bit in recent years, especially as more women have ascended to leadership roles at GM. Barra, The New York Times writes, was part of a generation of high-powered female executives who have helped make the company more woman friendly. And Barra's promotion, for it's symbolic value alone, should help that process along.

In the meantime, she has a resume that suggests she'll keep the company focused on making vehicles people actually want to drive. Back in September, outgoing GM CEO Dan Akerson hinted at Barra's promotion when he said one day GM would be run by a "car gal." Now it is. And that's kind of great.