English pop stars age quickly, as scientists know from carbon-dating Amy Winehouse’s lungs. But when mouthy British chart-topper Lily Allen first stomped over to the States with neon sneakers and a platinum (in England) debut, Alright, Still, she exuded the mischief-loving glee of a bratty little sister who’d never harden into a Dunhills-puffing divorcée. She slagged off celebrities, slept around, got high and wrote blog posts with titles like “Twats”—mostly for laughs. Y’know, just acting her age.

Allen was a 21-year-old built for the 21st century. Alright, Still instinctually fused hip-hop, ska, soul and swinging mod grooves into a sound as modern and multi-racial as her native London. She reclaimed locker-room bravado for girls, laughing about her ex’s small dick and fearlessly rewriting 50 Cent’s “Window Shopper” as a satire of grannies at the mall. And she did it all with a singsong chirp that made words like herpes and crack whore sound sweet.

Two years later, she’s no longer young enough to know everything. After too much post-success hard living—including a drunken cat fight with Elton John at an awards show—she’s developed an ambivalence about credit cards, one-night stands and other cheap thrills that once perked her up. “I’m not trying to say that I’m smelling of roses,” she sings in a sassy, vaguely Cockney lilt. “But when will we tire of putting shit up our noses?” She also worries, on the feminist anthem “22,” that girls’ lives end once they get really old—say, 30.

Allen should know—lately, she’s been preparing for her own premature obsolescence. After a surprise-pregnancy announcement in winter of 2007, she even decided to become a mom. (Sadly, she miscarried.) Now she’s delivered that rare thing: a grown-up album that’s also incredibly fun. Producer Greg Kurstin, who’s worked with Kylie Minogue, has helped Allen craft a bouncy, cabaret-influenced alternative to Minogue’s adult-contemporary dance-pop. And Allen is pondering more-adult dilemmas—like, how does a gum-smacking, club-hopping, smart-mouthing sprite prove she’s mature enough to handle domestic life?

For starters, she listens to the BBC now—and political one-liners make this album zing. There’s the George Bush protest “Fuck You” and sarcastic cracks about 9/11, blood diamonds and anti-depressants. Even her tirades against the famous feel topical: On the swirling synth ballad “Him,” she wonders about this “God” wanker who’s so popular these days. If her lefty-Unitarian politics sometimes feel too easy, watching a honey-voiced pop star move away from the bathroom mirror and out into the world still seems fresh. Just try to imagine Taylor Swift capping on Vladimir Putin.

Before she can act globally, Allen has to think locally. It’s Not Me features loads of family-oriented closet cleaning. The airy mid-tempo ballad “Chinese” suggests she’s used take-out night as ritual talk therapy with her rehab-alumna mom. And the clubby “Back to the Start” is a mea culpa for mocking her older sister—“the taller and the prettier one.” There’s less love lost with her father, actor and gadabout Keith Allen: Disguised as a song about making amends, the cabaret jaunt “He Wasn’t There” is actually a brutal list of all the ways he messed her up.

If Daddy was manipulative, he’s got nothing on Lily, who sabotages Kurstin’s arrangements like she’s spiking party punch. The country song “Not Fair” swaggers like Rawhide while Allen complains that her cowboy can’t get her off, even after she “spent ages giving head.” And on the anti-consumerism rant “The Fear,” she laments that she’s “a weapon of massive consumption” beneath a shimmery beat so catchy, it could help sell skinny jeans at Topshop.

That’s Allen’s charm: She offsets an assault of cheekiness with confessions so intimate, they could have been drafted during an A.A. meeting. Sometimes the vulnerability feels scary, sometimes it’s giddy, like on the sunny love song “Who’d Have Known,” which finds her spending drama-free nights with a new bloke—watching television, chatting about the weather, preparing for their future as an average middle-aged couple, just trying to fare better than their parents did. In the end, that’s Allen’s most grown-up epiphany. Love doesn’t have to happen in the club. Sometimes it happens on the couch.

Download “He Wasn’t There,” “Who’d Have Known,” “Not Fair”