Fall Out Boy presents a seemingly odd sonic stew.

First you have the public face of the band, pretty boy bassist Pete Wentz, who writes all the lyrics and whose easy-on-the-eyes looks make fans out of teeny boppers who otherwise would be into the latest boy band.

In a one-hour show at the Warfield in San Francisco last night, Wentz talked to the crowd between every song, tossed himself into it at the end, and otherwise made a school district's worth of teenage girls--and maybe even some of their parents--swoon.

But here's the rub: Wentz isn't the band's front man.

In fact, save for the occasional yell for punctuation, Wentz doesn't really sing.

That job falls to Patrick Stump, whose shy-round-guy look belies a powerful-yet-melodic voice. Yeah, Wentz writes the lyrics, but the unassuming Stump makes them sing.

Fall Out Boy's music is best categorized as pop punk, but each band member has a long enough resume in the Chicago hardcore scene to refute any thoughts of coattail riding. Last night's set largely split between songs from the band's major label debut, 2005's From Under a Cork Tree, which spent 72 weeks on the Billboard 200 chart, and its forthcoming album, Infinity on High, which hits stores February 6.

It dutifully included breakout hits from Cork Tree like "Dance, Dance" and "Sugar We're Goin' Down," as well as crowd favorites like "Champagne For My Real Friends, Real Pain for My Sham Friends."

Wentz and guitarist Joe Trohman tossed themselves furiously about the stage, while shirtless drummer Andy Hurley pounded adeptly on the skins.

That fans loudly sang along to songs that won't be in stores for another month comes as no surprise, of course, especially for a band with as ravenous a following as this one.

But it was the new material that showed the band's interest in spreading its wings beyond the power chords and the sweet-but-barked lyrics. "This Ain't a Scene, It's an Arms Race," the first single off Infinity, is a sing-along foot stomper, complete with a bit of profanity for emphasis.

The new tracks proved that Fall Out Boy is no one-fad-wonder.

Permanent Me, the Early November, and New Found Glory opened, with the latter upping the energy in the building tenfold. The South Florida group's pop-punk comes with a swagger as evidence that they've been around for nearly a decade, headlining the Warped Tour in both 2002 and 2004.

The remaining Fall Out Boy tour dates:
1/5: Anaheim, CA - The Grove of Anaheim

1/6: Tempe, AZ - Marquee, Theatre

1/7: Albuquerque, NM - Sunshine Theater

1/8: Denver, CO - The Fillmore Auditorium

1/10: St. Louis, MO - The Pagent

1/11: Cleveland, OH - Agora Theatre

1/12: Toronto, ON - Kool Haus

1/13: Boston, MA - Avalon

1/14: Philadelphia, PA - Electric Factory

1/16: New York, NY - Hammerstein Ballroom

1/17: Washington, DC - 9:30 Club

1/18: Raleigh, NC - The Ritz Theatre - Disco Rodeo

1/19: Atlanta, GA - Tabernacle

1/20: Orlando, FL - Hard Rock Live