Editor's Note: The Life & Arts senior staff combed through this year’s pop culture and selected the artists, albums, books and movements that they think, in one way or another, helped define 2011. This is the second in a two-day series.

Jay-Z and Kanye West’s relationship lends itself to a big brother-little brother comparison. Jay is undoubtedly the big brother: always unflappably calm and confident, he radiates a remarkable quiet charisma that reportedly can instantly silence a room full of people, and which presumably comes from knowing that you’re said to be the greatest rapper of your time.

Kanye, then, is the little brother: spoiled, attention-seeking, self-involved, prone to tantrums, energetic to the point of hyperactivity, trying desperately in his own outlandish way to live up to his mentor. His messy, self-indulgent posturing undercut by occasional fits of disarming honesty and introspection makes him a strangely endearing figure.

On their own, each man is currently a defining voice in music and the wider world of pop culture in their own right. When paired together, the two have created an album that, despite (or perhaps because of) its overall incoherence and propensity to indulge Kanye’s more theatrical tendencies, is an incredibly fun musical space to hang out in.

Released in August, Jay-Z and Kanye West’s collaborative album, Watch the Throne, has essentially dominated the bulk of my musical life for the past four months. I have yet to tire of it, despite the fact that it’s become a habit to give the album a full listen-through every couple of days, and it seems I’m not the only one. Watch the Throne has proved a point of fascination for countless others this year, expressed through blogs, Twitter feeds and the current success of their Watch the Throne U.S. tour. Although Watch the Throne is ostensibly a fairly equal collaboration between Jay-Z and Kanye West, the album ultimately has Kanye all over it. His penchant for meticulous, opulent production is present almost to the point of over-saturation, and his deft, bombastic rhymes, like “luxury rap, the Hermes of verses/sophisticated ignorance, write my curses in cursive” can’t help but overpower many of Jay-Z’s lyrical contributions.

Which isn’t to say Watch the Throne is just a Kanye West album that happens to feature Jay-Z. Their back-and-forth throughout the album is electric and thrilling, a vital part of why Watch the Throne is still addictive four months out and counting. The entire album was recorded in person, with both men in the studio together, and the resulting chemistry is powerful.

This chemistry is realized in the video for the single “Otis,” which features Jay and Kanye performing in matching denim and white in front of a desert warehouse, practically giddy with shared energy: Jay-Z repeatedly throws a brotherly arm around Kanye’s shoulders, Kanye wildly launches himself around in the background while Jay raps into the camera, and Jay smilingly mouthing along with Kanye’s words, seemingly unable to help himself.

Their — dare I say the word — bromance is so winningly adorable it’s almost sickening. It’s the playful partnership between big brother Jay and little brother Yeezy that makes Watch the Throne a defining album of 2011.