LOS ANGELES: "You walked into the party like you were walking onto a yacht. Your hat strategically dipped below one eye. Your scarf, it was apricot."With those descriptive lyrics more than 30 years ago, singer-songwriter Carly Simon created one of modern music's great mysteries - who, exactly, was being dissed in "You're So Vain"? While Simon may never let the riffraff in on her secret, she's made global headlines this week by auctioning off the answer to one lucky (and rich) man - NBC Sports chairman Dick Ebersol. Ebersol offered up $50,000 at a charity auction to win a private concert for 10 with Simon, along with a lunch of peanut butter and jelly sandwiches to be washed down with vodka on the rocks. But the crowning moment of the exclusive rendezvous at Simon's Martha's Vineyard home is her promise to tell Ebersol who Vain is really about - after he signs a confidentiality agreement. Top contenders are ex-boyfriends screen legend Warren Beatty, Rolling Stone Mick Jagger (who sings backup on the song), then-husband James Taylor, and folk-singer Cat Stevens. The mere suggestion of an answer to the vintage riddle caused a media fervor, giving Simon, Ebersol, and charity auction organizers Martha's Vineyard Community Services, which raises money for a variety of social services agencies on the island, a big dose of high-profile press. Charity reps appeared on Today to talk about the auction, and the story was picked up as far away as South Africa. So Simon wins PR Play of the Week for garnering massive attention from an ancient-history mystery, and Martha's Vineyard Community Services gets kudos for creative fundraising, hard-core Simon fans get only condolences because Simon isn't likely to let the Cat (or whomever) out of the bag - at least to general audiences. Curious, huh? You really want to know who that song is about. Don't you? Don't you?