Here's the info straight from Ernie Ball regarding the annual event:

The Ernie Ball Company is providing your band the opportunity to perform at the most prominent live music festival of the last decade. Beginning June 25th and culminating August 19th, our Battle of the Bands will showcase the very best local bands at the 10th anniversary of the Vans Warped Tour. Four bands from each venue will be selected to play live on the Ernie Ball Local Heroes Mobile Stage. Equipped with a 24,000 watt sound system, Ernie Ball's Local Heroes stage has featured over 5,000 unsigned bands including national acts Bowling For Soup, Nonpoint, and Story of The Year. Sign up your band at http://battle.ernieball.com