Please remember that these are rumors, and to take this with a decent amount of salt.
Alright guys, here's a little tidbit from my source.
Apparently, this ex-forgeworld employee is certain that Chaos will get new Special Characters.
They will not be in the first wave of releases, but will be in the Codex. He's suggested that most of the rumors we're seeing (no new Special Characters rumor) are based on the first wave of model releases, not on actual Codex content.