This applies to everyone EXCEPT for those attendees who attended Comic-Con this summer as a child but will be 13 as of 1 November. They must try to pre-register along with everyone else - and they still need their badge to do so. In other words, kids who got in free this summer for being kids will stop being kids in CCI's eyes if they've turned 13 by 1 November. If that's your offspring, save their badge - they'll need it.
Now, as far as needing your badge for pre-registration - that's still going to happen next year. By which I mean the pre-registration in 2014 for the 2015 Con. The switcheroo this year is just a last-minute change marketed as a courtesy. Oh Comic-Con, never change.