In the last few years, Pitchfork Media has been recognized for the mixed blessing it bestows on indie music culture. Since its inception over a decade ago, the site's commitment to covering as much music as possible is unimpeachable; there are dozens, if not hundreds, of albums that might have languished in obscurity were it not for Pitchfork's staff, and thousands of people who have significantly expanded their music collections with the site's help.

But Pitchfork's vast readership has given their reviews an astonishing amount of power, and they have launched the careers of many musicians into orbit very prematurely. For every duly championed underdog, there are several bands not quite ready for the demands an 8.8 or a 9-point-whatever album rating can suddenly generate.

It's still difficult to gauge just how helpful those ratings are to new bands, but it's equally hard to underestimate the effect Pitchfork's had on indie America's music tastes and attitudes. There are few spots on the Internet where broadening one's musical horizons is so easy, and last weekend, at Chicago's Union Park, the Pitchfork Music Festival brought that same opportunity to life. Nearly 17,000 people came out over three days, most of them to take in something new rather than revel in the presence of established favorites, and the festival accommodated its crowds brilliantly. Thanks to savvy scheduling and yeoman's work by the sound engineers and roadies, the downtimes between acts were remarkably short, and there were rarely moments when one band's set took too many listeners away from another.

Yet the smooth technical ride placed most of the festival's lineup in a strange position: under the glare of the sun and the withering gaze of thousands of people who were unfamiliar with their material. Even on Friday, ostensibly a celebration of three well-established, critically revered albums (maybe even "classics," depending on who you talk to), most people seemed there just to see what all the fuss was about.

For bands still coming to grips with their ascendance to indie stardom, it was a tough spot to be in. Vampire Weekend looked and sounded genuinely queasy for most of their set, and it might've gone down as one of the weekend's worst sets had their drummer not willed his bandmates into form at the end. A few other bands, like Fuck Buttons and HEALTH, didn't acknowledge their surroundings at all, turning in sets that ignored both the audience and the outdoor acoustics.

Even established acts, like Ghostface Killah and Raekwon, seemed dissatisfied by the ignorance of the crowd. Dizzee Rascal scolded his audience after their lukewarm response to his hit "I Luv U" ("I seen you lot listenin to dat folk music bullshit - man fuck dat! We gotta be live-o!"), and !!! frontman Nic Offer was similarly displeased in the early going. But both performers read the crowd correctly, earned their audiences' trust, and turned in superb sets that people talked about all weekend - Dizzee slowed his songs down perceptibly, allowing Wiley's influences (two-step, American hip-hop, and reggae) to breathe more freely, and !!! made their set all about rhythm. Nearly every song began and ended as a martial, deafening stomp, and the audience loved it.

But throughout the weekend, the festival highlighted an increasingly common quandary for indie artists. How well can electronic music be performed in such a setting? Does it have a place in a festival setting? There didn't seem to be one single answer, but success correlated strongly with veteran experience: Caribou, who has metamorphosed from a hunchbacked laptop clicker into an impassioned band leader over the years, presented a wonderfully tight set built around live percussion (he brought three drummers along to help), while High Places and Fuck Buttons both turned in sets that sounded weirdly pre-recorded. Though both groups make drone-y, vibrating music that plays wonderfully with space, both sets felt confined, with every sound issuing from the same location.

Bradford Cox's side project Atlas Sound sat somewhere between these two extremes. Despite an ominous introduction ("I have no idea what I'm going to do. I really hope this doesn't suck..."), Cox sounded more in control of the heap of gadgets that lay before him. Layers of echo and reverb rose, crested, and evaporated, and each wave expanded the landscape it evoked. His audience had trouble anticipating when songs were about to end, but they sounded hugely appreciative each time.

Of course, the best came last on both nights. The festival's unquestioned peak came on Saturday, when Animal Collective obliterated the crowd's expectations with a fluttering, kaleidoscopic set. The songwriting styles of Avey Tare (David Portner) and Panda Bear (Noah Lennox) have grown brutally different in the last few years, but under the lights, an illusion of solidarity was created. The band mechanized their songs, quantizing their drumbeats and weaving their songs' elements, reduced to samples, together with the dexterity and patience of a top-flight DJ. The band sewed several new songs into this fabric too, and these tracks - with their bright, liquid mutations and clean sound - both held Portner and Lennox's songs together and elevated them.