I was relieved by the verdict, since I did not see any basis for claiming that Zimmerman had been shown to be guilty beyond a reasonable doubt, which is supposed to be the standard of proof in criminal cases. But I find the commentary, mostly online, depressing. As best I can tell, practically everyone believes he knows what happened and argues from that belief. I may be the only person in America who does not.
As best I can tell, the evidence is consistent with Zimmerman's story--that Martin attacked him and was on top of him beating his head against the concrete when Zimmerman shot him. If that story is correct, the shooting was done in self-defense, so neither murder nor manslaughter. That is true whether or not the confrontation was a result of Zimmerman following Martin around suspiciously.
But while the evidence appears consistent with that story, I don't think it is inconsistent with other stories, in particular with a version according to which Zimmerman started the fight. If he started the fight and could have ended it by letting go of Martin and running away, then the shooting was criminal. Since that could have happened, comments that depend on the confident assumption that Zimmerman's story is true are unjustified, just like comments that depend on the opposite assumption.
But it appears that very few people are willing to accept "I don't know" as a valid conclusion.