In the Experimental Rules section of the new Contemptor pattern Dreadnought from Forgeworld, I found this passage: -
A Space Marine Contemptor Dreadnought is an Elites Choice in
a Codex Space Marine, Codex Dark Angels, Codex Space Wolves,
Codex Blood Angels or Codex Black Templars army. Until a
specific variant of this unit is featured in a forthcoming book, the
Contemptor as listed here may also be used in a Codex Chaos Space
Marines army.
To me, the last sentence is a hint that Chaos Space Marines might not be far off. What do you guys n gals reckon?