Sitting in a winged armchair at the back of a converted Camberwell pub, Fearne Cotton has a mobile clamped to her ear and is talking at breakneck velocity. She sounds surprisingly tough and formidable - a brief but revealing look at another facet of this preternaturally jovial and, dare I say it, bubbly television presenter.

She comes off the phone, we greet and she is back in perky, peppy mode - the Fearne you get on TV, vivacious, gregarious and upbeat. Not only does she talk fast, every sentence ends with an exclamation mark. (If you look on her MySpace blog this is exactly how she writes, too.) This is the Fearne you expect from watching her on Comic Relief or Guilty Pleasures, a persona that no doubt led to her being picked out of the blue to present NBC’s Last Comic Standing, a comedy talent show, after producers saw her on a Guinness World Records one-off. She is, as they say, on the cusp of breaking America.

And she might just do it. Fearne is a bit more edgy and rocky than girl-next-door Cat Deeley, less pneumatic and cheesecake than Kelly Brook (despite admitting to eating chocolate every day, she has a wiry frame), less robotic and sterile than Kate Thornton and not as sardonic, smartarsed and smug as Alexa Chung. There is a genial blokeishness to her vocal intonation that comes in handy, I would imagine, for schmoozing male rock stars, though her silky-blonde, bigeyed looks are vanilla enough for children’s TV and Comic Relief.

Perhaps it was this mix of cheeky and squeaky clean that landed her the only interview with Princes William and Harry last summer before the Concert for Diana? “I was shitting myself,” she says, with a manic eye roll. “I thought they were going to be standoffish, but they were almost exactly the opposite. If anything, they were eager to please.” She admits to being flabbergasted when they admitted to listening to the Radio 1 request and chart shows she presents with Reggie Yates “and they love Moyles, too. They were adorable. William is just like someone you could go down the pub and have a few drinks with.

Well, he isn’t, of course, but you know what I mean”.

It’s probable that William, if he is typical of most twentysomething guys, wouldn’t mind going down the pub with Fearne, either. Today, for the Style shoot in the pub, she has soft, whitish-blonde hair that has been rollered into loose Farrah Fawcett curlicues. Her big, expressive eyes, which dart about constantly, are framed by unblemished skin. For the shoot, she slipped on a bottom-skimming navy and white dress with superhigh red ankle-strap shoes, and she’s now wearing a vintage black Siouxsie Sioux T-shirt, a sparkly black chiffon blouse (also vintage) and a pair of spray-on black jeans. Despite the saucy/black rock chic, Fearne still looks like the sort of girl who smells nice.

She is comfortable company too - markedly confident and assured for a 26-year-old. A lot of women are a morass of low self-esteem in their twenties, but I sense Fearne has grown up fast. Like Britney, she was doing Disney Club as a teenager; unlike Britney, she hasn’t cracked up under the strain of (an admittedly lesser) stardom.

“I interviewed Britney when we were both 16,” Fearne says. “She had just released her second single, I was still doing Disney Club, and we were both teenagers chatting away, fine and normal. I can’t believe what’s happened to her now.” She stops and assesses their differing trajectories. “I’ve been lucky, in that I’ve had it all really slowly, and I’m still making a gradual climb towards wherever I’m headed.”

Fearne isn’t part of the cool-girl, indie-pop clan that includes Kelly Osbourne, Chung and Peaches Geldof, but this is probably further evidence of her well-adjusted nature. Her only “fellow celeb” friends are Holly Willoughby, whom she met in children’s television almost a decade ago, and Jake Humphrey, a sports presenter. She says her best friend is a singer-songwriter who she has known since she was 12, and another is a nanny. “I don’t really hang round in those celebrity circles,” she says. “I think if you’re friends with celebs and you get on well, then wicked. But I can’t get with the idea of being friends with people because you’re all famous. It’s just bizarre. I like to separate work and normal life. For me, it’s not about where you hang out, or being in the cool place. I couldn’t give a crap about all that.”

Still, surely Fearne, the girl Robbie Williams chatted up on screen during Live 8 (he asked her to come and live with him in LA, with his dogs), has some tales of pop-star bad behaviour? “What I like about Robbie is that he is unpredictable and doesn’t say what he is supposed to,” she says, laughing. “You get that with Liam and Noel [Gallagher], too, and Amy Winehouse. That is what rock and pop are supposed to be about. You get so many people who are just telling you what someone has told them to say, and it is really boring.”

Did she get asked on a date by Prince William? “No - I couldn’t believe that when I saw it in the Daily Star the week after. We only talked about Radio 1 and the weather. The rest of the time there were, like, 20 royal secretaries buzzing around us.”

But she did date Luke Pritchard, lead singer of the Kooks? “No, but we did hang out for a while. It’s funny: I interviewed him recently and it was rather weird.” She doesn’t say why, but it is an intimation that something passed between them. She does admit to dating Ian Watkins, lead singer of Lostprophets, but her current squeeze of two years is the former pro skateboarder Jesse Jenkins. “He’s only 22, my toy boy,” she gurgles affectionately. They met in a bar (“I thought, ‘Wooh, he’s nice’ ”) and they live together when they are both in London. Jesse is originally from LA, so they have been back and forth to America all year - which jars with Fearne’s avowedly green politics. “My carbon footprint is awful, flying to and from LA,” she groans, adding that she is obsessive about switching off lights before bedtime and that “nobody should be using plastic bags any more”.

Before I met Fearne, I expected her to be a bit edgier than her on-screen persona might suggest. Now I’m not so sure. “On Friday, I’m going to see Reef,” she admits, without a hint of shame at liking the chugging rockers. “That’s a step back in time, isn’t it?” Despite her predilection for translucent NHS specs, penchant for vintage clothing and eclectic taste in music (Led Zep and White Denim to the Ting Tings and Cajun Dance Party), I’m not sure you could ever call her icy cool. “I’m off to my nan’s for tea. She’s barking mad,” she announces as she slips into a big-buttoned, blousy-sleeved camel coat and heads out of the door. Girl next door with edge, that’s her - mixed with, I imagine, more than a soupçon of steely determination.

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