According to Nuclear Blast and the Deathstars Facebook- Bone has been replaced by Oscar Leander of Crescendolls. Why Bone left is unknown- though as far as I've been told, they are all still friends and Bone is welcome should he ever want to return.
Bone apparently left back in 2010. The band only announced his leaving a couple weeks ago. However, those who had seen them on tour Boneless had said it was quite obvious Bone had been replaced without even being told.
Sad news indeed, but unfortunately true.
Even though Bone will never see this--
We will all miss you for sure.