Looks like we get a little more details:http://www.equestriadaily.com/2012/05/e ... -list.html
Everfree Northwest is proud to present Ponystock, the first ever music festival devoted to all the spectacular FiM-inspired compositions across our community. Held throughout the three day convention, Ponystock features live performances of over two dozen musical guests from around the world, playing everything from folk and rock instrumental sets to epic club remixes and electronica.
The festival's central attractions include nightly thematic concerts showcasing the best our community has to offer. The list of participating musicians continues to expand, but includes artists such as:
Dethonator the Metal Brony
I Bring Da Lulz
Jeff the Strider
Yelling at Cats