I think the "stand your ground" policy is a complete red herring - the duty to retreat, or lack thereof, isn't really the material issue here, and I wholeheartedly agree that people are blaming that policy based on an agenda and not based on the merits of this case. The big question here isn't whether Zimmerman retreated, but rather the question is whether he had a reasonable belief that his life was in danger. Another potential issue in my mind is who initiated the conflict, since it was Zimmerman who began following Trayvon. If Zimmerman didn't have a reasonable belief of imminent bodily harm or if he initiated the conflict, he can't really argue self defense, at least not in any fashion that would absolve him of any and all charges. However, neither of those determinations is affected whatsoever by the lack of a duty to retreat (i.e, the "stand your ground" policy). As such, I think the anti's are just using this incident as a convenient way to attack Florida's self defense laws.
For my $0.02, I think there are sufficient facts in this case that Zimmerman should have been arrested, and I think the Florida PD messed up by not arresting him. I'm not saying he's definitely guilty and should be punished, as that's for a jury to decide, but rather I think there are sufficient facts out there that cut against Zimmerman to support at least a charge of manslaughter. I completely expect that, barring circumstances that paint a completely obvious self-defense scenario, I will be prosecuted should I ever have to discharge my weapon in self defense. The facts here aren't all against Zimmerman, but they aren't all in his favor either, and this is not a clear cut case of self defense. Rather, it's shades of gray, and it's worth remembering that self defense is an affirmative defense. To not bring charges in the first place given the facts of this case seems like a clear mistake in my mind, and it's anyone's guess as to why they chose not to (and there are plenty of people guessing as to why). Once charges are brought, all the facts can then be gathered and presented and he can argue his case of self defense to a jury (if it even makes it that far). By not making the arrest when the facts supported it, they've brought tons of attention to this case and given the anti's a way to attack Florida's strong self defense laws, even though the policies they're attacking have very little to do with these circumstances (i.e., the stand your ground policy).
In any event, it's my understanding that the Florida state attorney will bring the case to a grand jury on April 10th and they'll decide whether to go forward with an indictment based on the evidence presented, so we'll find out what happens then. In the meantime, I guess we'll have to hear about people protesting and twisting the facts, all while blaming a "stand your ground" policy which isn't even the material issue in this case.