I've always felt that Audioslave is too clean, too accessible, too 'mainstream' to be considered a continuation of either RATM or Soundgarden. I enjoy it to an extent, but for me, it doesn't resemble punk or grunge very much. Perhaps it is closer to modern hip-hop sonically, except with non-auto-tuned vocals. Compared to Soundgarden, it's not very ambitious or experimental.
Should we consider Audioslave a continuation of Rage Against The Machine, Soundgarden, or something 'new'?
Audioslave
RATM
Soundgarden