Katy Perry Part of Me is scheduled to open in theaters tonight (Thursday), but few have high hopes that the 3D concert film featuring America's most popular new female singer will reflect her success on records. (She has sold 11 million CDs worldwide.) Sill, the film, from Paramount's Insurge label, reportedly cost less than $15 million to make and should earn around that amount between now and Sunday. The film has generated mostly decent reviews. "Lots of rock star highs, Russell Brand lows and a whole lot of bubbly music fill up this frothy bit of show and tell," writes Betsy Sharkey in the Los Angeles Times . A.O. Scott in The New York Times finds the film more interesting than similar concert films featuring Justin Bieber, Miley Cyrus and the Jonas Brothers. And the reason for that, he writes, is that Perry "just has more talent than any of them, and her songs have a wider emotional range. But the film also catches glimpses of the unraveling of her marriage to the British actor and comedian Russell Brand, which gives it an undercurrent of classic backstage melodrama." But Elizabeth Weitzman in the New York Daily News argues that all that behind-the-scenes stuff is not primarily what Katy's fans buy theater tickets to see. "For audiences, the most valuable aspect of concert movies like these isn't the star's carefully crafted personal promotion. It's the chance at relatively cheap front-row seats for a show you never got to see live (or loved so much you want to see again). And Perry's stage presence is undeniably irresistible," Weitzman writes. And Mick LaSalle in the San Francisco Chronicle appears to be as Charmed by Perry as her young fans. Her songs are good, he writes, likely because "they address what it's like to be a young person in this decade, and I'm pretty sure that, if I were 16, I'd see Perry as some kind of goddess."