Playing dress-up is fun, but maybe it's not the best idea for a fledgling anchor suffering from low ratings and a lack of gravitas. That anchor: Katie Couric. TV insiders are agog at Couric's decision to show up at her 50th birthday party, held Saturday night at Tiffany & Co.'s Fifth Avenue flagship store, in an outfit modeled on Audrey Hepburn's look in Breakfast at Tiffany's. (The theme was a play on CBS's somewhat outdated nickname, The Tiffany Network.) Guests reportedly received invitations with drawing of Couric-as-Hepburn and favors from Tiffany's; they were also invited to try on jewelry during the party.

"It was all very Marie Antoinette," snipes one source.

And it's not as though Couric is reigning in the ratings. After an initial surge at the start of her tenure on CBS Nightly News, viewership has fallen, and the broadcast now draws fewer viewers than it did under former host Bob Schieffer. Critics blast the hostess for her ever-changing appearance and her headstrong backstage demeanor. (Couric-boosters decry this as a sign of blatant sexism.)

But one official from a rival network was less taken aback by Couric's Hepburn getup than by her choice of venue. "It basically made her an endorser of, and a hack for, Tiffany's," he says.

A spokesman for Couric notes that the details of the party were planned not by the anchor but by her friends and that guests were invited to donate to Couric's pet cause, colon cancer research, in lieu of gifts. As for the Marie Antoinette jab, he demurs, "Gratuitous, sexist, anonymous, ill-informed potshots are not worthy of a response."

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