Looks like Atticus and John Hillcoat talked on set of Ice Age a bit
http://www.billboard.com/articles/bu...view/id/113100
Ross is also scoring the documentary Crocodile Gennadiy and John Hillcoat's Triple 9. And his score for the biographical Brian Wilson film Love & Mercy includes ambitious mash-ups of Beach Boys tracks and electronics. It opens in June.
Afaik, Nick Cave was down to do the score originally, so it might be another collab chance (Nick Cave allowed his music to be used on 12 Rounds' Jitter Juice and they were both on the Days of Grace OST), or Atticus might be taking over.