By Cheryl Eddy

THE BACKSTREET BOYS are over, 'N Sync's been trampled by Justin Timberlake's solo career, Britney Spears has morphed into a Madonna-smooching tabloid queen, and Christina Aguilera's dubious fashion choices grab more attention than her singles these days. But before you breathe easy, know this: as one wave of bubblegum pop stars crashes and recedes (leaving behind debris like Newlyweds and Joey Fatone's movie career), another rises, hoisting anew squeaky-clean performers primed to rake in the kind of cash slobs like you and I will never see in a lifetime.

That thought may be depressing, but the music's sure trying not to be. Consider 16-year-old Hilary Duff's new CD, Metamorphosis (Buena Vista), which is filled with upbeat anthems of empowerment and daily affirmations for the driver's ed set. "Listen girl, gotta know it's true / In the end all you've got is you," the budding guru explains on "Inner Strength," one of two cuts written by Duff's older sis, Haylie. The other, "Sweet Sixteen," presciently notes, "And I've got friends who love me / Bright stars shine above me / My blonde hair is everywhere." And yeah, it really is, what with the album hitting number one its first week out, all those Lizzie McGuire Movie billboards, the outpouring of MTV love (heavily rotated videos for "Why Not" and "So Yesterday," appearances on Diary and Punk'd, etc.), and even a Hilary Duff Metamorphosis Visa gift card, available in amounts up to $100 and usable at "millions of Visa locations worldwide." Next, perhaps, are outlets plying the planned Stuff by Hilary Duff line of clothing and makeup. Young fans don't seem to mind being hit from all sides by officially licensed Duff-abilia, but the situation can't help making one wonder: is she a girl or an amazingly lifelike robot engineered by those who are getting rich off her every move?

Keeping it lite

Conspiracy theories notwithstanding, Duff's not doing much to assure skeptics she has a soul, or even a pulse. Despite her recent split with star makers Disney, she's still dead set on making her name a trademark, à la the Olsen twins – the tween industry's gold standard. Of course, all the fame hasn't gone to her (blond) head. "It's weird that my name would be on something and make someone want to buy it," Duff told USA Today this summer. "It's crazy, because I'm such a normal teenager." Mmm-hmm.

Musically, Duff's sound is kind of Avril "the anti-Britney" Lavigne lite, a comparison helped along on some tracks produced, arranged, recorded, and mixed by shared knob-twiddlers the Matrix. But while Lavigne poses as a faux punk, Duff's snarl-free collection of tunes isn't trying to make anyone rage against the machine ... or even their parents. The songs are aimed squarely at kids with more, er, suburban concerns: falling in love, falling out of love, love explained with mathematical metaphors ("If you can't do the math / Then get out of the equation"), and so on. Harmless, sure, but Metamorphosis's significance in the music biz beyond money-making, manufactured product goes about as deep as a smear of lip gloss.

Serious bubblegum

At least, at the very least, rival double-threat Mandy Moore seems to have set her artistic sights a little higher. The 19-year-old's latest disc, Coverage (Epic), offers up versions of ear-candy classics like Joe Jackson's "Breaking Us in Two" and John Hiatt's "Have a Little Faith in Me." Moore, whose transformation from blond to brunette was, in all likeliness, a calculated bid to be taken more seriously, has a pleasant if breathy voice that's more distinctive than Duff's, and she's certainly working with stronger material. But Coverage is hardly a throwback to the radio days of yore; unfortunate production choices – turntable scratching on "I Feel the Earth Move," cheesy effects throughout "One Way or Another" – ensure that the album sounds au courant to a fault. While overproduction is the norm for pop stars of all ages these days (see J.Lo and Cher embracing the vocoder), Duff's and Moore's new albums are dripping with enough technical wizardry to make a person wonder what's going on behind the curtain. The deliberate muffling of any (if any) vocal talent does much to support the idea of teen star as prepackaged goods. The airbrushed image is at all times protected – by parents, managers, label execs, evil overlords, whoever – from delivering the kind of raw, honest performance that would certainly mean career suicide. You think Britney Spears ever sings live?

Cinematically speaking, Moore – who lacks Duff's background in TV – has shown a bit more range beyond twinkly-ness: she dies young in A Walk to Remember and gets all sullen-adolescent in How to Deal. Still, both stars clearly have similar criteria when it comes to choosing roles. No Thirteen-style dramas here: upcoming projects for Moore and Duff include, respectively, a romantic tale involving the First Daughter and something that needs no explanation beyond its title, A Cinderella Story.