December 15, 2008 – In the wee hours of a warm November morning, a piercing sound fills the cramped control room of Studio C at Miami's Hit Factory. Wreathed in smoke, with a long spliff hanging from his lips, Lil Wayne rocks back and forth, staring intently at the fingers of his left hand as they dance across the neck of a blue Gibson electric guitar. He plucks the strings with his right thumb as he tries to wheedle out licks to go with the thick, thumping beat he laid down earlier. After several minutes of noodling, Wayne removes the blunt from his mouth and exhales plumes of smoke through his nose. "Mwah, mwah, mwah, mwaaaah," he sings, mimicking the sound of the instrument. "That's how I learned to play," he says. "I match the guitar to my mouth." Wayne first picked up the guitar about two years ago and boasts that he's never had a lesson.

October 21, 2008 – Anonymous message board postings aren't exactly a reliable barometer of public opinion, but anyone who logged on to iTunes on August 24 to buy the site's sixth-most-popular song couldn't help but be struck by the near unanimity of attitude toward the track in question. "Ahhh this STINKS! Why is it in the top 10??" wrote "coleenybeany. "THIS IS TERRIBLE!!!! PEOPLE ONLY BUY THIS CUZ THEY DESPRETLY WANT THE SONG!" offered "rickie H Lime." A poster going by the deceptively erudite moniker "PoliSciBA" chimed in with "iTunes s-u-x winkies! What a joke." The comment board beneath iTunes' 17th-most-popular song was a similar cavalcade of gratuitously punctuated, caps-lock-crazy vitriol. Surprisingly, neither track was the work of Pussycat Dolls or Nickelback, or any other polarizing figure likely to incur copious dollops of online scorn simply for existing.

September 22, 2008 – Caleb Followill needs a dentist. The day before the biggest gig of his life, the 26- year-old Kings of Leon frontman is standing outside a boutique hotel in London, flanked by his bald, tattooed bodyguard and his girlfriend, a thin, dark-haired model named Lily Aldridge. Down the block, a handful of onlookers nod toward Followill, who has a gray trilby tilted low over his heavily stubbled face and a maroon Jordache T-shirt and skinny black jeans tightly covering his ropy frame. "I've been grinding my teeth," he says, climbing into a waiting car.

August 5, 2008 – On a Sunday in April 2006, Gary Harris pulled up to D'Angelo's large starter mansion outside Richmond, Virginia, in a limo. Harris, the A&R man who'd first signed D'Angelo in the early '90s and who had overseen his 1995 debut, Brown Sugar, was on a mission: to escort the singer to Eric Clapton's Crossroads Treatment Centre in Antigua. As he walked into the spacious kitchen, Harris knew this wouldn't be easy. Spread across the kitchen table, marble countertops, shelves -- nearly every available flat surface -- were empty alcohol bottles of all conceivable varieties. "There was scotch, vodka, beer," Harris recalls. "While I was waiting for him, he emptied the contents out of the corners of three or four bottles to get a shot." D'Angelo himself was unshaven, about 40 pounds overweight, and hadn't packed. "He was trying to act like he didn't know I was coming that day," Harris says.

March 26, 2008 – Deafening screams echo off the walls of the large gymnasium at South Carolina State University on this evening in late January. Flashbulbs pop. People jump up and down, shaking hand-lettered signs reading WE WANT CHANGE and S.C. STATE LOVES BARACK over their heads. Near the front of the stage, beneath a lectern adorned with a blue STAND FOR CHANGE banner, an army of camera-phone-wielding teens and twentysomethings jockey for position as a handsome black man appears. Ladies and gentlemen, please welcome...Usher! The man who's sold nearly ten million copies of his 2004 album, Confessions, takes the stage sharply dressed in a gray sweater, jeans, and a khaki jacket with the collar popped.

February 1, 2008 – Bobby Ray Simmons was an early bloomer. At an age when most kids are still mastering the finer points of tag, the man who would later be known as B.O.B. was mapping his future. "In kindergarten I had to draw a picture of what I wanted to be when I grew up," the Atlanta-based MC says. "I drew a rapper. I didn't really know what a rapper was or what they did -- I just wanted to do it." He figured it out soon enough. By middle school he was toting a notebook filled with rhymes and posting his own stanzas on Internet rap forums. Such ambitions didn't necessarily impress his classmates. "All through my life, I was hated on," he says. "When I was in middle school, they used to write in my rhyme book, 'You suck' or 'This sucks.'" His cousin taught him how to craft beats with the software Fruity Loops, and by 15, B.O.B.

January 5, 2008 – October 10, 2007, is a day that will live in infamy in the hearts of major-label executives. That was the day Radiohead, after more than a decade with Capitol Records, self-released their seventh album, In Rainbows, digitally, without a price tag. The same day, news broke that Madonna was leaving Warner Bros., her label since the early '80s, to sign with Live Nation. Her deal cedes percentages of her touring, merchandising, licensing, and CD and DVD revenue to the concert promoter in return for a cool $120 million. Notably absent from both equations, at least at this early stage, was the mention of any traditional record label.

November 22, 2007 – Getting an audience with Lil Wayne is tricky. Interviews are pushed back, postponed at the last minute, and often just canceled. But it's not late-night partying keeping Weezy occupied: Dude is working. His latest album, Tha Carter III (Cash Money/Universal), caps off an astonishingly productive two years for the 25-year-old New Orleans MC (born Dwayne Carter), which has seen him churn out rhyme after rhyme for mix tapes, other artists' songs, or just to give away online. When we finally catch up with him in Atlanta, he holds up a CD-R. "I've done 18 songs in the past two days," he says. "I'm in the studio every night." Don't you have any other hobbies? I haven't found nothing that excites me more. Pussy, no. Money don't even do it for me. I hate strip clubs, so that's not what I'm going to do. If I ain't onstage, I'm in the studio. I'm only going out when you pay me.

November 15, 2007 – In the back of a tour bus parked outside Amos' Southend Music Hall in Charlotte, North Carolina, in early October, All Time Low singer Alex Gaskarth sits barefoot, his knees pulled almost to his chest, his nose and mouth buried deeply in a Vicks Personal Steam Inhaler. Between deep breaths from the small humidifier, he works his voice up and down a scale. "Zoo zoo zoo zoo zooooo zooooo." Deep breath. Gaskarth usually starts warming up his voice an hour before stepping onstage, slowly working it from the lower range he speaks in to the higher range he sings in. Today, he's struggling. "Aaaah-ooooooh-aaaah." He coughs, then blows his nose. "Shit, it's so breathy. It's fatigue. I've been partying too hard." Voice problems notwithstanding, Gaskarth is doing all right.

July 19, 2007 – Photographs by Greg Kadel "Wanna go to Hooters?" asks Interpol guitarist Daniel Kessler as we step outside the W Hotel in Dallas onto the sunbaked sidewalk. Kessler is a short, skinny 32-year-old with slightly nervous eyes and thin lips that begin to curl into a wry grin as he delivers this lunch invitation. His band -- which also includes singer/guitarist Paul Banks, bassist Carlos D, and drummer Sam Fogarino -- is on a nine-date North American tour leading up to the release of their third album (and major-label debut), Our Love to Admire, and the guitarist seems anxious to playfully tweak their resolutely cosmopolitan, sometimes painfully hip image. The Hooters in downtown Dallas is not just any Hooters. It is, Kessler informs me, the largest Hooters in the world.