There's very little in this video that leads me to believe that this was not an act of deliberate homicide. We'll see what the investigation comes up with but I'm betting that as with most police involved murders there will be no charges and the officer will be returned to duty.
Oddly this video makes the Rodney King beating look like a hand shake and cab ride home. I'm not sure why on earth the citizens of SF haven't torn the subway system apart. Hopefully cooler heads will continue to prevail and justice is indeed found in this case but I would imagine that won't be the case.