Just for the record, Guster isn't a jamband. It's hard to pinpoint exactly when it happened, but sometime between their 1999 major label debut Lost and Gone Forever and their Saturday show at the Starland Ballroom, the Boston trio managed to squeeze out their jamband juice. So as Guster ascended to the stage in suburban Sayreville, New Jersey, no one in the audience expected them to engage in much improvisation. But Guster's Christmas Charity gig did offer more than a few holiday treats and enough set list asterisks to appease the evening's straggling hippie-rock aficionados.

Though the jamband moniker never really meshed with the trio's sound, Guster did grow up in a jamband neighborhood. Playing a mix of organic pop and slightly quirky folk, Guster carved their northeast niche through ten years of incessant touring. During that time, the Tufts-alumni shared the stage with many jam acts, including moe., Strangefolk, Galactic, and Widespread Panic, with whom they toured for several months. In the studio they also hooked up with several hippie-heroes, including Karl Denson and Page McConnell, both of who helped flesh out Guster's classic guitar and bongo instrumentation on Lost and Gone Forever.

Building a dedicated fan-base on varied set lists, humorous stage banter, and high-school theatrics, it almost seems like Guster should have been a jamband. Their fans traded tapes and recorded set lists, using the internet and word of mouth to foster a close-knit community. But slowly thing began to change. Gradually electric instruments began to creep into their organic sound and quirky instrumentation was replaced with more straightforward, but equally enjoyable, hooks and chords. Set lists began to stagnate and radio festivals replaced "Guster Rep"-only shows as annual events. Yet Guster never seemed to sell out; instead they embraced their inner pop tendencies. Not that New Jersey's largely suburban audience knew about Guster's caterpillar club days.

A brand new theater, which lost its live music virginity two shows before Guster, the Starland Ballroom still sparkles. Its wood is shiny and serine, as if it's waiting for spilled beer to transform it into an average ballroom. In many ways Guster is a fitting band to help deflower the venue. After all Guster is in many ways the "gateway drug" for jam-music; an important stepping-stone between pop rock and Phish. Gazing over the evening's crowd, whose median age was 16, one could slowly see Phish shirts and Dave Matthews tie-dyes creeping in the audience's Abercrombie uniforms.

Opening with "What You Wish For," the first track on their definitive major label debut, Guster's audience carefully echoed their choruses. Throughout their two-hour show, the group drew mostly from their latest releases Lost and Gone Forever and Keep it Together, many of the same songs the trio has been touring behind for several years. Surprisingly, though, Guster is playing tighter than ever, using its underground energy to rip though road-staples like "Demons" and the newer, emo-edged single "Amersterdam." With Jo Pisapia, from Joe Marc’s Brother, featured as a road-show ringer, Guster expanded their sonic palette immensely. Pisapia played around with an eclectic array of instruments, including steel petal, keyboards, and electric lead guitar, a dramatic departure for the acoustic based band. Percussionist Brian Rosenwerchel guided the group through a strobe-heavy version of "Airport Song" and an impromptu performance of "Great Escape," from 1997’s Godfly. Not only has the percussionist shown amazing growth on his bongos and woodblocks, but he has also mastered the traditional drum-kit, helping the group transition into true pop-rock music. Red Oyster Cult," the group's first real rock song, comes complete with a drum roll and radio-friendly chorus. Yet the song's conventional feel only masks songwriter Ryan Miller's most revealing lyrics ("Call your mom on the telephone/tell her you're coming home / tell her there's not a chance you're ever going to change the world.") As they near their 30s, Guster has accepted its place in pop culture, yet its members still hold on to their adolescent sense of individualism.

Despite their high-school tendencies, the rowdy crowd did engage Guster, throwing ping-pong balls during "Airport Song," as is tradition, and calling out for the group's older, sparsely played gems. Packing their set lists with some rarities, including the Goldfly hidden track "Melanie" and the rarely played ballad "Two Point For Honesty," Guster also embraced their youth. "Come Down Stairs and Say Hello," Keep it Together’s emotional centerpiece, hinted at the group’s ability to compose multi-part story-songs and the bouncy "I Spy" did end with a groovy mini-jam. "Backyard," Keep it Together’s finest moment, would not sound out of place on Parachute, the group's acoustic debut. Yet it was beefed up with bass, banjos and a Dylanesque harmonica solo that added weight and depth to the song's structure.

Throughout the show, a few embarrassing moments did mar the audience's ethos. During opening act Stephen Kellogg's set, the crowd screamed in approval until they were told that he was not pop-icon Howie Day and some drunken high-school student threw a used condom on stage near the show's close. Unfortunately, unlike their peers, Guster's fan-base has not aged with the band, freezing their audience around age sixteen.

At one point during Guster's set, Miller offered his audience a "choose your own adventure" option for the show's song-list. At times Guster seems to be living out a similar storybook, straddling mainstream-radio rock and underground organic-pop. But despite their constant balancing act, Guster has been able to turn out consistently enjoyable live-shows. After all, one never gets too old to rock the suburbs.