02/08 Tool 02/11 Jeff Mangum 02/17 of Montreal 02/29 Blind Pilot 03/31 The Naked & The Famous 05/14 M83 and I Break Horses 05/19 Flaming Lips, Young the Giant, Dawes and AWOLNATION 06/07 Bonnaroo 2012!!! 06/13 Roger Waters 07/28 Toadies
He's playing Jazzfest so he's definitely a possibility.
Don't think he has played Roo in a while, either, so wouldn't be shocked at all if they brought him back.
Relentless7 with Ben Harper were there in 2009. I think having an album with Charlie Musselwhite makes it likely, especially since they're doing other festivals together. I'd be surprised if they're not there.