Katy Guest: Oh, my God! Oh, my God! Oh, my God!

Once upon a time fame was a thing apart. When superstars were invented they were equivalent to goddesses: glacial, aloof and 20ft high on a cinema screen. We loved them because we could not touch them. That was why we called them stars. The modern sleb is something different. We don't like people who act famous, like Pete Burns sneering in a gorilla coat or Rula Lenska in leopard-print pants. A few days after Chantelle walked out of the Big Brother house as the nation's favourite slebrity, Vanessa Feltz explained why. "Who cares a damn that Chantelle can't sing, dance or act?" she wrote. "All any celeb really needs is a likeability/vulnerability factor." We want them ordinary, she meant. We want them dull. We don't want them to be just like us any more; we want them to be us. Only even more ordinary than that.

A few years ago, The Independent considered running a competition. It would be known as "A Talentless Contest" and only the truly hopeless could apply. The paper wondered how challenging it could be to make an everyday moron into a star, but we decided it was a bit crass.

Fortunately for Chantelle, they were not so morally superior down at Endemol, the company that makes Big Brother. According to its chairman, Peter Bazalgette, Plan Chantelle was "a very clever joke by our production team. It was a kind of slightly post-modern, convoluted joke". It did not take a work of genius to convince a room full of lip-glossed no-hopers that this lip-glossed no-hoper was one of them. But they did choose cleverly in Chantelle. The 22-year-old is about as far from being famous as it is possible to be. She is not superior: she thought Dundee was in Wales and has never heard of a gynaecologist. She never assumed she was worth it: the poor girl shouted "Oh, my God!" 40 times when she won. She wasn't even exceptionally pretty. Compared to her, most viewers must have felt like superstars.

Chantelle is loving her fledgling fame. She has been photographed staggering out of nightclubs, showing what can happen to young women who still regard free champagne as a generous novelty. She has been dolled up in a couture dress (and then taken out of it) by The Sun. The Daily Star says: "She deserves to be famous. She's a natural." The Daily Mail is calling her "an Eliza Doolittle for our celebrity-obsessed age".

But she ought to be careful: the British public has given birth to another legend, but it has a habit of eating its own young. She only has to turn the page with her nipples on it and check out the images of Kate Moss to see what happens to ordinary girls made good. In the baptism of fire that is the Big Brother house, she has amply demonstrated that she can "be herself". What she has to show now is how she reacts to "being famous".

It is perhaps inevitable that, once we make Chantelle famous, we will chop her off at the knees. She should enjoy it while she can. The girl from the Wickford omnibus is 2-1 to record a UK No 1, her used lipstick looks likely to sell for a fortune on eBay and she is set to earn £1m in the next year. She has been on Richard & Judy. And a road is about to be named after her. Chantelle Houghton is the most famous nobody in Britain. Oh, my God! Oh, my God! Oh, my God!