"Maybe old is the new naked"

In less than a week, some of the world's top models will stomp down the runways at New York Fashion Week. Many are in their teens and early 20s, but this year, older models will be lighting up advertising, reports CBS News correspondent Vladimir Duthiers.

Joan Didion is back in print, but not with a new novel or essay. Luxury fashion brand Céline tapped the literary giant for what The Observer calls "the ad heard round the world."

"She is an American icon; possibly a fashion icon," famed photographer Juergen Teller said. He snapped the chic eighty-year-old.

"She always has a very stylish way of dressing herself," Teller said.

The shot falls squarely into a mature movement that's currently sweeping advertising.

"There are certain women -- Joan Didion is one of them. It's amazing. And it just blew up on social. I mean, it's really got so much attention," Grey Advertising executive creative director Alice Ericsson said.

Attention grew when Saint Laurent released ads of 71-year-old Joni Mitchell.

She may be 93 years old, but Iris Apfel is as busy as ever, modeling for both Kate Spade and Alexis Bittar this season. L'Oreal has added Twiggy and Helen Mirren to their already-stacked roster of mature spokeswomen, including Jane Fonda and Diane Keaton.

"They're icons. They're amazing," Ericsson said. "They have substance. They also have wrinkles."

They've got wrinkles and 50 shades of grey hair.

"We've gone from literally hot, you know, and, like, sexy, sort of trashy looks, to cool," Ericsson said. "And to be cool, you need some character, whether it comes from wrinkles or from books you've written."

In its newly released spring 2015 campaign called "Better than Ever," Barneys is celebrating the allure of women of a certain age.

"The message of the campaign is that a woman can command a room, in a way, more effectively and more powerfully when she's in her 40s or 50s or 60s than a young girl in her 20s," Barneys creative director Dennis Freedman said.

He chose the ladies for this sexy shoot, including former model and industry mentor Bethann Hardison.

"Celebrating the older woman as sexy and alluring is absolutely on time, it's spot on," Hardison said.

Barneys has used older faces before, but this time the heat is rising. Some of the photos were a butt cheek too saucy for network television, but right on message for the luxury brand.

"What we're trying to say is this: 'You have a long life and this life is a rich life, and this life doesn't end at 25," Freedman said. "That's a very, very important message to send to millennials."

Advertisers are chasing millennials, Ericsson said, hoping to build loyalty with a group on their way in, not out. But consumers over 60 spend more than $8 trillion a year. That is expected to nearly double by the end of the decade.

"This is a really important demographic and these women have all the money and all the buying power," Ericsson said.

Certainly in beauty, she said, boomers want to see themselves represented more.

"When we hired Ellen, there were a lot of anti-aging creams being sold with literally 16, 17-year-olds," Ericsson said. "In a few short years, it's become unacceptable to have an 18-year-old."

She said wrinkles don't sell, but they get attention.

"If you take that new Dodge commercial they just did, every one of them was just wrinkled beyond repair. and it's a spot that you see it, and you love it," Ericsson said. But if at the end of the spot they were selling you a skin cream, you'd go, 'no thanks.'"

Like Dodge, carmaker Fiat used aging actors in its Super Bowl commercial. Seasoned gentlemen are seeing screen time, too, by Dos Equis and Speedo, which is looking to broaden its appeal in a new ad that says, "I am 91 years old. I'm a master swimmer."

The ads showcase faces lined with wisdom and humor, grey hair lending gravitas and life experience making a woman more desirable.

"I think it's a fad that will continue," Ericsson said. "At one point, at Tom Ford, everyone was naked. Maybe old is the new naked."

CBS News has confirmed that 83-year-old Carmen Dell'Orefice will be opening the Elie Tahari show at New York Fashion Week.