Most everything has been covered here, except for the fact that some lines were not allowed to form (for whatever reason) until a specified amount of time.
The line where I was was chaos. It was allowed to form at 6am. One minutes before that the police and mall security were driving people away. Some folks even got detained (by the police) for not heeding their warnings.
So 6am rolls around and there is a mad rush. Apple employees yelling, mall secuiry yelling, police yelling. The police ended up calling backup because the two (yes TWO) officers they had couldn't get control of the situation. Finally they picked a random guy to be the front of the line and people shuffled in behind them.
I was in the area from about 7pm the night before. I was 400 something in line; there absolutely without a doubt were NOT 400+ people there when I first arrived at around 7. My situation had nothing to do with me not getting i line at the right time. I would have been first, and if not first, among the first dozen or so.
I don't know in what world it made sense to the mall, Apple, or whoever else was involved to start a line at 6am and not expect a mad stampede to happen. Had they allowed the line to form spontaneously like every other even I have ever been to in my life (Apple or not), this could have all been avoided. The way they did it they may as well have just had people put their names and numbers in a lottery up untila given time and then received a text with what order they would be in line... that is basically what happened except with a whole lot more time wasted.