For Advertisers, It's Bottoms Up

When it comes to butts, large is in charge.

Ever since Jennifer Lopez (search) and a bootylicious Beyonce (search) came on to the scene, women have been flaunting their womanly backsides ... and Madison Avenue has taken notice.

Nike's new ads have women bragging of behinds big enough to be "space heaters in bed," and Dove's new campaign has caused a debate over the use of "real bodies" in advertising.

"It's attention-getting, it's humorous, it's playing in to a woman who wants to be strong and independent," Allure magazine publisher Nancy Berger Cardone told FOX News.

But it's more than that. Advertisers are banking that these ads will grab women ready to celebrate what they've got.

"Most American women are size 12 and up. So, I just think it's Madison Avenue types taking advantage ... [they] want a bigger piece of the pie out there," image consultant and entertainment reporter Annie Hoffman said.

So what is it about big butts?

"I think thanks to Jennifer Lopez, having a larger derriere has become the 'in' thing to have. It used to be an ample bust, now I think it's an ample derriere," said Hoffman.

As for whether it's a smart business move on Madison Avenue's part, Hoffman thinks, and hopes, it is.

"They're trying to relate to the average woman that's out there, because most people are not a size 6 or 8. I really want this to be successful, because I think there are a lot of young girls who have eating disorders, and I think there are a lot of women who may be suffer from lower self-esteem because they don't look like a lot of the women modeling on the magazine covers."

But that's not to say that thin is no longer in.

"I think that there's still going to be spikes of the population that still likes to see glamorous and sexy and beautiful thin women, because you guess deep down we probably think we'd like to still be like that," Hoffman added.

Bottom lines are already brimming from the super-sized trend: Some women are shelling out as much as $500 for just the right pair of bum-hugging jeans.

In fact, Jessica Simpson (search) has even been accused of padding her formerly flat butt to play curvy Daisy Duke in the "Dukes of Hazzard" movie.

So women -- don't be afraid to shake your decidedly diet-deprived booty.

"If it's your butt, show it off, if it's your arms, show those off. I think that right now we're in a time where there's not one size and one shape that is considered beautiful," said Cardone.

FOX News' Jamie Colby and Brenda Buttner contributed to this report.

Click on the video box near the top of this story to see a FOX News report.