Bands that adopt the former approach tend to make a lot of money for a little while, until their audience gets bored of hearing the same thing over and over. Bands that take the latter path tend to have staying power, not to mention a semblance of artistic credibility -- if their audience keeps up with the changes.
Switchfoot's 2005 release Nothing Is Sound was a solid success, its fat post-grunge guitars supporting searching, philosophically-minded lyrics on cuts like the minor hit “Stars.”
You can hear the difference from the first thrashy/trashy notes of the opening title track, as the band sets aside its penchant for slightly slick, undeniably muscular anthems of the soul and latches onto a wide-open, crunchy garage-rock sound full of jagged riffs and furious drumming. The lyrics are serious-minded, but more abstract than anything on 
Switchfoot songwriter/frontman Jon Foreman’s anti-materialist streak comes to the fore on the similarly frenetic “American Dream,” surely one of the most danceable political statements of the decade. “I want to live and die for bigger things / I’m tired of fighting for just me… Red, white, blue and green / But that ain’t my
“Dirty Second Hands” is where you begin to sense how far the guys are reaching, a spooky, close-miked, echoey ode to isolation and dislocation full of harshly plucked notes and ominous vocals. Not that they’ve abandoned the stadium-scaled philosophizing of Nothing Is Sound completely -- the soaring “Awakening” is one of the boys’ very best U2 homages, a powerhouse, singalong spiritual anthem. But then they follow that familiar sound with “Circles,” a bravura cut that features guest vocals and mandolin from Sean and Sara Watkins of newgrass heroes Nickel Creek. First mixing quietly urgent verses with slamming, Zeppelinesque choruses, it builds to a thundering crescendo before dropping back to a beautifully arranged prog-folk coda that feels like a misplaced snippet of circa-1971 Yes.
Continuing to mix it up, the boys delve into raucous, Jet-like guitar rock (the loose, giddy “Amateur Lovers”), a dreamy, eerie story-song (“Faust, Midas And Myself”), and urgent, jittery, New Wave-influenced rock (“Burn Out Bright”). Lyrically, Foreman expands his field of vision as well, managing to turn out an actual love song (“Head Over Heels”), though he invests the latter with a contrary, unsettled edge that’s both true-to-life and resonant (“You’re everything that’s fair in love and war”).
Somewhere in the middle, Switchfoot cleanses your between-course palate with perhaps the biggest surprise, a sublime, mid-tempo, chiming-guitars elegy (“Yesterdays”) that sounds like nothing so much as Bono fronting Out Of Time-era R.E.M. Similarly subdued, closer “Let Your Love Be Strong” sums up everything that’s appealing about Switchfoot in general and this album in particular -- a steadily evolving arrangement, passionate vocals and a thoughtful lyric (“Maybe I’m just idealistic to assume that truth / Could be fact and form / That love could be a verb”).
Mixing things up and taking real chances, Switchfoot shows courage and growth on Oh! Gravity, eschewing the sure thing they might have settled for, and instead issuing a diverse disc that challenges their audience. Not quite a masterpiece, Oh! Gravity is nonetheless a brave, impressive and thoroughly entertaining piece of work.