The teen takeover is, of course, the norm nowadays, with Justin Bieber declared the third most powerful celebrity in the world by Forbes in 2010, but it was the post-millennium surge that started it all.
However, what happened to the teens who kicked off a celebrity revolution? Did they manage to bridge the gap between adolesence and adulthood in the public eye, or have their careers taken a nosedive since they left their teen years?
The High School Musical cast
Disney's made-for-television movie High School Musical became the surprise smash hit of 2006 and, never ones to shy away from popularity, the Mouse House soon turned it into a trilogy.
The franchise made massive stars of previous unknowns Zac Efron, Vanessa Hudgens and Ashley Tisdale, but not all have made the transition to adult stars.
Efron's good looks and smart choices meant he has had the easiest progression, and will appear in the ensemble rom-com New Year's Eve this December, alongside Michelle Pfeiffer, Ashton Kutcher and Sarah Jessica Parker.
Hudgens and Tisdale haven't fared so well, and it's not for want of trying. Flop films and cancelled TV series mean the actresses are threatened with obscurity if they don't sign on to a winner soon.
The Harry Potter gang
Thrown into the spotlight as 10-year-olds when cast as Harry, Ron and Hermione, Daniel Radcliffe, Rupert Grint and Emma Watson have now been bona fide celebs for more than a decade. The last film in the Harry Potter series premiered last summer, but it remains to be seen whether the young actors can escape their ubiquitous alter egos.
Watson is starring in the upcoming My Week With Marilyn, albeit in a minor role, while Radcliffe is pursuing a successul career in theatre. Grint has four films in production, and was widely tipped to have the most lucrative post-Potter career, but time will tell.
Best of the Rest
> Hilary Duff Ms Duff is now literally up the duff. Pregnant, married to hockey star Mike Comrie and having left all the trappings of her teen television, movie and pop careers behind.
It seems her newlywed status may hinder her in Hollywood as she was rumoured to have been dropped from the upcoming remake of Bonnie and Clyde due to her pregnancy clashing with filming.
>Lindsay Lohan Barely a day goes by without Lindsay taking up column inches, but it's due to her battles with the law rather than any career highs.
She's had more mugshots than most career criminals and been in and out of rehab for numerous addictions, but it doesn't seem that the girl who had such potential in Mean Girls will be regaining her once red-hot career any time soon.
>The Jonas BrothersAnother product of the Disney school of success, the Jonas Brothers were hugely popular in the late Noughties.
Purity ring-wearing New Jersey boys, they were sweet, squeaky clean and heart throbs to millions.
Eldest brother Kevin is now married, middle sibling Joe is attempting to forge a solo career and youngest Nick, still a teen at 18, is dating Delta Goodrem.
> Miley Cyrus She is now legally an adult at 18, but still a teenager in years, if not in mindset. In 2008 at the age of 15, she was ranked the most powerful teenage celebrity in the world by Forbes, thanks to her hit series and 3D movie as alter-ego Hannah Montana, and a set of controversial snaps published in Vanity Fair in which Miley bared her back for photographer Annie Leibovitz.
Determined to leave her tween-tastic past behind, Miley has stepped out of the spotlight to work on more adult roles, and appears to have toned down her headline-grabbing and raunchy onstage antics of recent years.
She appears to have realised that acting like an adult doesn't mean dressing like a cougar, but is she leading lady material for a new generation, or will her legacy forever be down to her adolescent success?