All premiere's are like that. You need to know somebody, or if you work for a fan site or something, Disney will give you a press pass. The public will stake a spot on Main Street and watch the celebrities go buy.
Fantasyland and Tomorrowland will be open. DL closes at 5:00 PM, DCA closes at 11 PM. I suggest stay the night there so you can get up at 5:00 AM and get in line to go inside.