WE'VE ALL heard of cover songs, but is it possible to cover a wardrobe? That's what Katy Perry and Riff Raff did at the MTV Video Music Awards on August 24. The pair sported denim outfits similar to the ones Britney Spears and Justin Timberlake wore at the event 13 years ago.

I suppose 13 years is a pretty long time in pop culture history—it does seem like a lot's happened in the years since Spears and Timberlake were a couple whose individual celebrity shares of stock were valued equally. A lot's happened for Perry as well: Her 2001 false-start incarnation as a Christian performer—under her actual name, Katy Hudson—is a distant blip in the rearview, and her risqué lipstick-lesbian anthem "I Kissed a Girl" from 2008 seems loveably quaint today. (Fun fact: Katy Perry performed on the Warped Tour that same year, alongside bands like the Color Fred and Forever the Sickest Kids, whom she probably hasn't kept in touch with.)

The idea, ostensibly, was that Perry and Riff Raff wore those VMA outfits as homage to Brit-Brit and JT—a shortsighted pop-culture enthusiast's idea of a royal couple. But the ridiculous clothes seemed closer to a spoof; the two resembled a pair of out-of-season Halloween revelers. In fact, Perry's career could be looked at as one continual pageant of ever-changing Halloween costumes. (Riff, on the other hand, found a single and particularly horrific uniform—Bo Derek cornrows, Mike Jones grill, '90s-Prince zigzaggy facial hair, distressingly bad rap skills—and has mostly stuck with it.)

What Perry might not realize is that she doesn't need to reference Spears at this point in her career. She's on track to be a bigger pop star than Britney Jean ever was. (Timberlake's crown, meanwhile, seems relatively safe from the clutches of Mr. Raff.) Although Spears has cumulatively sold a few million more units than Perry's current total, her career of bestsellers also stretches almost a full decade longer than Perry's. It's likely that, even in this era of soft music sales, Perry will surpass her before long. Perry's 2010 album, Teenage Dream, became the first non-compilation album since Michael Jackson's Thriller to contain five number-one singles; a sixth, "Part of Me," appeared on an expanded, double-dip reissue of that album. Last year's Prism hasn't done quite as well, but "Roar" and "Dark Horse" are two of the best-selling singles of not just recent years, but of all time.

Spears was probably a formative influence for Perry, who was 15 when "...Baby One More Time" hit number one in 1999. (It's worth noting that Max Martin, the writer/producer for "...Baby One More Time," co-wrote Perry's two breakout hits, "I Kissed a Girl" and "Hot n Cold." He also litters the credits of Teenage Dream and Prism.) And Spears is a reference point for Perry much in the same way Madonna was for Spears and her contemporaries—but whereas Madonna was a pop-art provocateur, the Disney pack of 1999 were manufactured chart fodder. Perry also has more natural charisma than Spears. Yes, it can be difficult to get a read on Perry beneath the endless array of costumes and personas in her videos and live performances. But all those Barbie-doll dress-up games draw out Perry's personality, rather than conceal it.

She's a terrible actress, but a game and funny one. The video for "Birthday"—aside from some regrettable attempts at Yiddish humor—is weirdly charming, as Perry dons a series of Bad Grandpa-like latex getups and goes undercover at various birthday parties. And the video for her current single, "This Is How We Do," might be her clearest statement of purpose yet: It features an almost senseless amount of costume changes, including a Mondrian dress and a pizza-pattern bathing suit, before it degenerates into a bunch of dancing animated GIFs of ice cream. It, like Perry, is gaudy, confusing, and oddly likeable.

Let's hope that the recent Prism, then, is an anomaly for her. The album, while including such goofs like "This Is How We Do" and the jet-breeze lux of "International Smile," also gets bogged down in some unfortunate garbage. Plagiarizing Prince's finest "I Wanna Be Your Lover" funk-guitar riff can't keep "Birthday" from sounding like a commercial jingle, and "Unconditionally" is unrepentant, overwrought glop. (She also pronounces the title "UN-cond-i-SHUN-a-LEE," resulting in the worst verse scanning since Alanis Morissette, another '90s touchstone.) The more serious Perry gets—and Prism gets pretty serious, particularly during pity parties like "Ghost" and "Double Rainbow"—the more she sounds like an anonymous wannabe on The Voice. Playfulness needs to be Perry's MO.

But the shortcomings of Prism—and Perry's iffy taste in boyfriends, who include John Mayer and, possibly, Riff Raff—are all part of learning how to be a gigantically famous pop star, one might suppose. Some are well equipped for the long haul (Madonna), while, for others, the wheels come off pretty quickly (Spears). Perry, despite not always trusting herself to put her best foot forward, seems to have a pretty decent handle on things. She's got a sentimental streak a mile wide, which would be a liability if her girlish playfulness didn't trump it. And she's got an exceptional voice; it sounds good even when pushed to its histrionic limits.

Amazingly, there's still room for Perry—one of the most ever-present pop stars of the past few years—to stake out her own identity, both visually and musically. It's clear she can do the Bowie/Madonna chameleon thing effortlessly, but her pop-culture skins often reference what's come before, rather than staking out new turf. (A recent internet meme suggested that many of Perry's looks were pilfered directly from '50s Archie Comics character Katy Keene, and the vast similarities are uncanny.) Perhaps the real question is this: If, in a decade or two, some pop starlet dresses up like Katy Perry for an awards show, will we catch the reference?