It's not an indication of screentime. According to certain sources, only half of those characters should have major roles. Two 'main' characters, maybe three, and not necessarily the ones we would expect.
That being said, I hope that the characters who, like Nadine, got shafted in the original run will have a wonderful…

http://www.smh.com.au/enter… Here's Mark Frost saying it's everything but. And judging by the scarce leaks… it seems he's not bullshitting.