Photo by Jason DeCrow/APReleased online as financial markets took a historic plunge, the full-length collaboration between Jay-Z and Kanye West revels in self-described "luxury rap." Two of hip-hop's biggest stars tell us in rhyme form that even in this economy, they can afford fine art, haute couture, even top-tier German home appliances.If you can forgive these self-satisfied rap titans their name-checking of Mark Rothko, Dries Van Noten and Miele, though, "Watch The Throne" has more on its mind. Celebration of the high life is undercut by regrets, loneliness, and snatches of mournful social commentary. Like West's acclaimed solo effort last year, the album title reveals itself as both boastful and paranoid, proud and furtive. Watch us on top, they seem to say, but know that we don't always like what we see from here — both looking outward and in."Murder to Excellence" encapsulates the theme in a two-parter that shifts beats halfway through. West begins by quoting an old Jay-Z line — "I'm from the murder capital, where they murder for capital" — to decry black-on-black violence in his hometown of Chicago. Jay-Z then describes ascending to "the new black elite" with Will Smith and Oprah Winfrey. "Only spot a few blacks the higher I go ... that ain't enough. We gon' need a million more," he raps.Isolation infuses the Swizz Beats-produced "Welcome to the Jungle," where West drinks away his struggles: "Just when I thought I had everything, I lost it all. So que sera. Get a case of Syrah, let it chase the pain." Jay-Z places himself in the shoes of fellow musicians at their lowest points, linking Eminem, Michael Jackson, Pimp C, 2Pac and more through coded couplets that reward repeat listening.Even more dour is the RZA-produced "New Day," with odes to sons the two may eventually father. Over a plinking piano and Nina Simone sample, West flagellates himself for mistakes, from his choice in women to post-Katrina telethon appearance, noting: "I'll never let my son have an ego." Jay-Z is even more direct: "Sorry Junior, I already ruined ya, 'cause you ain't even alive, paparazzi pursuing ya."Oh, poor millionaire rappers. Go cry into your Armand de Brignac Champagne at your yacht parties, you may find yourself responding. But this type of intimacy and honesty doesn't come easy — or often enough — in commercial hip-hop. West's feverish, sometimes needy soul-baring has jolted the oft-aloof Jay-Z to attention, just as his sped-up soul samples did the first time they worked together, on 2001's classic "The Blueprint.""Throne" is sometimes guilty of failing to let its lyrics breathe, as West and other producers drown out the duo's rhymes with distracting vocal samples or ever-escalating arrhythmic electro beats. "Who Gon Stop Me" is an ambitious but ultimately failed rap-dubstep mashup. The playful wordplay of "Gotta Have It" gets lost in the Neptunes' multiple James Brown samples. Beyonce showcase "Lift Off" wants to be a successor to West's regal, star-studded "All of the Lights" but feels incomplete, like it was ripped from an engineer's hands to beat a deadline.Moments of determined calm hit their target more effectively. Frank Ocean, part of the buzzy Los Angeles collective Odd Future, croons a soulful, effortless chorus on the gorgeous memoir "Made In America," an album highlight. He's joined by The-Dream on the provocative album opener "No Church In the Wild," filled with striking images and poetry.The 23-year-old Ocean's presence signifies the "Throne's" attempt to blend old with new. Despite all the nods to hip-hop history — "Apache" and "Top Billin" samples, quotes from Outkast and Wu-Tang — the 34-year-old West and 41-year-old Jay-Z have crafted a bleeding-edge nontraditional hip-hop album. Over the course of 12 songs (plus four bonus tracks in the deluxe edition) West has pushed his "big brother," one of hip-hop's few true legends, into riskier territory, sonically and lyrically, than he's gone in many years.Not including Jay-Z's R. Kelly collaborations — and really, the less said the better — these hard-working rhyme partners have touched on their genre's familiar aspirational themes repeatedly over the course of a combined 16 solo albums. On top, done counting their Basquiats and all-black Maybachs, they're left to assess: What else is there?