looks like there will be 3 stages.
the "getting there - by train" page states The Newark Penn Station stop directly connects to NJ Transit's Light Rail, which will bring concert goers directly to the festival grounds. i'm pretty sure this is wrong. from newark penn, one can take the PATH train to grove street and it's walkable from there (10-15 minutes) - but that's not "directly to festival grounds". alternately you have to transfer again to the Hudson Bergen Light Rail line and pay another fare. again, not direct.