Rapper Dr. Dre will close the 2012 edition of the Coachella Valley Music & Arts Festival, to be held for the first time over two consecutive weeks in mid-April. Headliners for the multi-weekend, six-day affair include rock acts the Black Keys, Radiohead and the Shins, as well hip-hop and dance acts Snoop Dogg, the Swedish House Mafia and Kaskade, among others.