New band of the day – No 902: Jessie J

Hometown: Essex.

The lineup: Jessie Cornish (vocals).

The background: That list of ones to watch in 2011 that we compiled the other day needs another addition – Jessie Cornish, alias Jessie J. We're not necessarily saying we like her, but we sense from her powerhouse of a voice and her hugely commercial songs that she is going to be massive. People in this country love big strong voices that hit high notes and blast you with hurricane force, and Jessie J's is one of those. And she can do it live, that other national preoccupation: it works unadorned, it doesn't need machines to make it sound "good". It is, technically, impressive enough to give Clare Maguire's people at Polydor a few sleepless nights.

But she's more than just A Voice. She writes, too – not just doodles in her bedroom; we mean songs. Hit songs. And not theoretical ones, either. She wrote Party in the USA for Miley Cyrus, which even grown-ups admit is a great pop tune. And she's from Essex! Girls from Essex don't write No 1 Stateside hits. Ask Daisy Dares You. But then, Daisy Dares You was more on a punk-pop, Avril Lavigne tip, and Jessie J, well, she has several modes on her 2011 debut album Who You Are, but they're all pretty au courant: she does grimy R&B on her Labrinth-mixed single Do It Like a Dude and retro-soul Ronson-style with added BoB on Price Tag. Nobody's Perfect is Lily Allen-ish feisty pop and Who You Are is the navel-gazing rock epic that could be big in America, and indeed could BE American, which is the holy grail, surely.

But hold on – how did this Essex girl get to have BoB on her debut album and write a No 1 for America's biggest teen sensation while also, unbelievably, co-writing songs for Alicia Keys (that's right: "for", not "with"). Long story. But it involves Cornish landing a role, aged 11, on the London stage in Andrew Lloyd Webber's Whistle Down the Wind, signing to Gut Records (aka the home of Right Said Fred) before it went bust, a stint with the famous William Morris Agency in the States, a showcase at the legendary Viper Rooms, meetings with R&B kingpin LA Reid before the 22-year-old then suffered a minor stroke and decided she really needed to get this party started.

At which point, she toured with Chris Brown across Europe, supported Cyndi Lauper, worked with hitmaster Dr Luke, and did some recordings that got Justin Timberlake, still recovering from gawping at Janet Jackson's breasts, to declare: "Who is the best singer in the world right now? Jessie J." Since then, celebs have been queuing up in cyberspace to praise her, with tweets from, among others, Kylie and Paloma Faith. She's even got her own online TV show, Dare Jessie, about to launch, in which fans will be invited to issue a series of challenges. We dare her to take on the Beyoncés and Pinks of this world, because from what we can hear, this is the first serious attempt on the part of a Brit girl to do just that.

The buzz: "We love you, Jessie J!" – every celeb in the world today.

The truth: Stomp, stomp, she's arrived!

Most likely to: Be treated like a lady.

Least likely to: Do it like a dude.

What to buy: Do It Like a Dude is released by Island on 2 December. She's live at XOYO in London next Thursday (11 November).

File next to: Pink, Beyoncé, Pixie Lott, Jodie Connor.

Links: myspace.com/jessiejofficial

Friday's new band: Jamie Woon.