I wrote a huge trip report featuring all of the artists I saw below with a few pictures, so check it out...
Matt Morris, What Made Milwaukee Famous, Newton Faulkner, Back Door Slam, MGMT, Battles, K'naan, Vampire Weekend, Dark Star Orchestra
Steel Train, Jose Gonzalez, Tegan and Sara, Minus the Bear, Les Claypool, !!!, M.I.A., Big Sam's Funky Nation, Anders Osborne, Metallica, Henry Butler and The Game Band, MSTRKRFT, Tiesto, SuperJam ft. Les Claypool and Gogol Bordello, Disco Biscuits, New Orleans SuperJam
Against Me!, Ozomatli, Mastodon, The Avett Brothers, Cat Power, B.B. King, Ben Folds, Iron & Wine, the everybodyfields, Pearl Jam, Money Mark, The Coup, Sigur Ros, Ghostland Observatory
Ladytron, Robert Randolph's Revival, Yonder Mountain String Band, Aimee Mann, Broken Social Scene, Robert Plant and Alison Krauss ft. T-Bone Burnett, Death Cab for Cutie