4 stages of music, i believe(mane, palomino, mustang, and appaloosa), one of those on the map is a mechanical bull or dance tent if memory serves.
and yes, headliners are on the "mane" stage. sometimes the palomino may have a headliner who is not quite big enough for the mane, but still pretty big name in general. for example, willie nelson played that stage last year.
first week in september, even got the ok from the missus to go to the all points west festival in nyc in early august, probably my last vacation for awhile...