I don't know how the trial of George Zimmerman will turn out but it doesn't make a difference. He's not actually on trial for the true blunder of being an independent crime-fighting zealot who aligned his persona with law enforcement to a tragic end. What needs to be elements in this case are things that likely cannot be, or more precisely, have not yet been.
For instance, did George really believe Trayvon was a significant threat or did Trayvon simply strike him as one because he was unfamiliar -- or worse, black? The goal would be to demonstrate that Trayvone wasn't actually acting in a manner that lives up to to George's characterization that he was acting particularly erratic. That George was just using the right keywords to justify the call he was making.
As to the black question, this is akin to asking if George acted out of racism. That's something I seriously doubt, although maybe it depends on how you define racism. There's nothing to indicate that George particularly hates blacks and he has in fact previously associated himself with their causes. On their behalf in fact, he actually has a louder record as a police critic. So no, I don't think that he sat around that night waiting for a black man to shoot freely under the cover of legitimate crime watch activities. However, he may have calculated greater sympathy for any confrontational action he might take in the particular case where a person is black, understanding a general culture of bias that would result in less scrutiny. A sort of "maybe I'm not prejudice, but fortunately, many other people are" mentality.
The other question that might shed light on his state is whether or not there was truly an uptick of thefts and burglaries within George's community in the period prior, as has been asserted since this story broke. Do the stats really show this?
Ultimately I am not sure George did anything legally criminal under Florida's construction of law. So long as there is a law on the books that says you can shoot anyone you feel confronts you irrationally and violently, it is, apparently, not likely that George broke the law. And, it appears that without a shred of evidence one way or the other to qualify the act otherwise, the law takes the word of the shooter. Indeed I'm inclined to believe at this point that Trayvon probably did come in swinging, which, if true, under "stand your ground", justifies the shooting (eyes rolling here). Of course if George was on the ground somehow dominated by the younger Trayvon, it would not even be a case of "stand your ground" -- but simple self-defense by that point. Assuming that it was not George's passive trap to be taken over by Trayvon in the first place.
None of that means George isn't guilty. George should be left feeling that this wasn't some just some big misunderstanding, but a direct result of his pursuit of reckless gratification. He was angry over what he saw as bad guys "always getting away" and "this time" he was going to do something about it damn straight even if that meant escalating matters until they got out of control.