nobody saw the Zimmerman altercation. Millions have seen this vid. There's absolutely no comparison.
But you can't help but to think how different it may have been if there was a similar video that showed the Zimmerman altercation in the same detail.
It may in retrospect have vindicated Zimmerman, but it may also have gone a different way....
The difference is that in this case, we can see and judge based on what the video shows did happen. In Zimmerman's case, as in many others, in the absence of video evidence, we are left with witness accounts and speculation.