Add another lineup to the ever-growing list of summer festivals: San Francisco's Golden Gate Park will host the inaugural Outside Lands Festival on August 22-24. And like the debuting All Points West festival in NJ, an "industry source" proclaims that Radiohead and Jack Johnson will headline, along with Tom Petty and the Heartbreakers. The festival is the brainchild of Another Planet Entertainment, a Bay area promoter, and Superfly Entertainment, the geniuses behind the Bonnaroo and Vegoose fests. No ticket details have been announced, though the event is expected to accomodate nearly 160,000 people. The Outside Lands fest should cement Rolling Stone cover boy Jack Johnon as the 2008 Festival King, having already secured headlining spots at All Points West, Coachella and Bonnaroo (and two nights at Hawaii's Kokua Festival, if you want to cover all bases). Stay tuned to Rock Daily for further details on this and all the rest of the summer's biggest concert blowouts.