This London advertisement knows your gender

(CNN) --- Here's a creepy-cool development in the marketing world:
A billboard that went up on Wednesday in London uses facial-recognition technology to know -- 90% of the time -- whether you're a man or woman. And it gives you a different advertisement depending on your gender.
Women who walk up to the billboard, which is located at a London bus stop and will be viewable for two weeks, are greeted with a 40-second film explaining the plight of women and girls in poor countries around the world, who often are denied eduction and opportunities that are afforded to men.
    Men, however, get a cut-down version of the content. They can't see the film, but they do get to see shocking statistics about the situation, like the fact that 75 million girls are denied education.
    Plan, the children's advocacy group behind the advertisement, says the goal is to highlight the opportunities that are afforded to men that women miss out on. This is the first time a gender-detecting ad has been tried in the UK, says Naomi Williams, Plan's campaign manager.
    Similar efforts have been tried before in Asia. In 2010, CNET reported on an ad in Japan that tried to read your age.
    Plan's bus-stop ad -- a throwback to "Minority Report," writes Megan Garber writes at The Atlantic -- uses HD cameras to take photos of people who stand in front of the advertisement and, importantly, who chose to have their gender detected. A computer program then "measures the distance between your features, such as the length of your nose or the length of your jawline," Williams says, and uses that data to determine, with 90% accuracy, whether you're a man or a woman. The camera only scans the faces of people who specifically opt in to view the ad, she says, and the billboard does not store any of the images it takes. "We do not gather any data and we do not store any data," she says.
    "In this instance, we are using this technology for good," she says. "We’re using it to get across a very strong and important message about discrimination. We’re looking for new and innovative ways to cut through the market and get to the consumer and their target market."
    What do you think? Is this cool and useful? Or just plain-old creepy?