Summer Sonic is announcing tomorrow which bands will play which date. It won't matter much for folks who are going all three days, but for me, who's planning on going to just one, this will have HUGE implications. It'll be either Saturday or Sunday for me, so I'll be pretty pissed if all the bands I want to see are on Friday.
They're also releasing the third batch of bands, although I imagine they've pretty much laid out most of their strong cards already. They might have something up their sleeves though.