Is Conde Nast teen social net Flip.com flopping? WWD reports that one of the site’s editors, Holly Siegel, has defected to rival Hachette Filipacchi’s Ellegirl.com and cites unidentified sources who say enthusiasm has been waning for the site. So far, monthly uniques have remained stuck at around 250,000 since the beta launch earlier this year, which WWD compares to rival Hearst’s Seventeen.com with 542,000 unique visitors in August. Flip’s publisher Jane Grenier presents a sanguine front regarding the site’s prospects, despite telling WWD that September and October traffic numbers are expected to decrease due to a suspension in marketing efforts while the site was being retooled. So, instead of focusing on uniques as a measurement for success, Grenier says that the site is pinning its hopes on engagement—the amount of time users spend on Flip. Users currently spend an average of 8.5 minutes on Flip, while pageviews per unique visitor have gone from eight to 15 pages per session. And though uniques remain relatively low, Flip is still able to attract advertisers, having added marketers such as Guess and broadcast TV network CW, which is teaming with Flip to promote its Gossip Girl series. As for building up uniques, Flip is starting a contest called Scholarflip, which will award money to be used for attending college. To spread the word among its target audience, Flip is working with a number of youth groups, including cheerleading association AmeriCheer and volunteer organization Do Something. .