I wonder if the reason so many people are vigorously defending Zimmerman in this thread is because it's not so much a referendum on an old cranky white guy -- we have plenty of those in this country -- but that it's by extension a referendum on whether Stand Your Ground laws are appropriate in the first place, due to the burden it places on society in determining which out of two people is telling the truth when one of them is dead.
I'm not certain I have a solid opinion on whether or not those laws should even exist yet. I don't have as much of a problem with "castle doctrine", where the assumption of dangerous malice is placed directly on the intruder; after all, it's pretty easy to avoid being caught on the wrong end of that, "don't enter people's houses uninvited and/or while they're unawares".
I'm not so enthralled with SYG laws however, as it seems to provide a convenient means for arguments to turn into killings without appropriate sanctions levied upon the remaining arguer. I would prefer that the presumption of guilt be placed on the initial person who chose to escalate the situation to deadly force, and that any or all involved parties be legally obliged to NOT initiate, but only respond in kind if deadly force is already present and known. This would of course mean that rather than hide behind SYG laws, the defense would need to provide more active proof of 'self-defense' in circumstances like this one -- and, in this one, it would require George to take the stand and give his version of events.