I just found out that the second stage/first stage stuff will be playing out slightly differently this time around than in the previous Ozzfests. All of the second stage bands will play before the first main stage band goes on. Also, the rest of the second stage acts have been announced:

Distrubed (headliner), The Union Underground, Systematic, Drowning Pool, Nonpoint, American Head Charge, Beautiful Creatures, Hatebreed, Black Label Society, Pure Rubbish, Mudvayne, Cold, & Taproot.

That’s rather a lot of bands, if you ask me. :) They join the main stage bands Marilyn
Manson, Slipknot, Papa Roach, Linkin Park, Crazy Town and festival headliners Black Sabbath.