He said, "OK", and, as far as we know, he broke off pursuit.
Pretty tough to claim self defense if you are actively chasing someone even if they lose you and then surprise you.
If the person you were watching is pissed off and feeling dissed that you were watching him and starts pounding on you as a result, then you are within your rights to kill him. That's more or less what Zimmerman claims happened. To convict him of a crime, you would have to disprove his version beyond a reasonable doubt, the opinions of Jesse Jackson, Al Sharpton, and Barack Obama and legions of MSM talking heads and Twitter morons notwithstanding.
Of course, it could have all been a horrible mistake. Perhaps Martin confronted Zimmerman, they exchanged words, Zimmerman went for his phone, Martin thought it was gun, ... well you get the picture.
We have proof, however, that Martin idolized a convicted murderer.
So, my bet is, Due to justified outrage at being profiled for walking while black with his hands in his pockets while wearing a hoodie, Martin lost it and unjustifiably jumped Zimmerman and starting beating the hell out of him. Which turned out to be a fatal mistake, since Zimmerman was packing and had stronger hands.
End of story. And justice requires that Zimmerman walk even if Miami burns. Issue miniguns to the Korean grocers!
He said "OK" within ¼ minute of leaving his truck. That is not compatible with the location of Martin's body.
In a gated community?
Let's be fair a moment shall we?
Get a 'white boy' walking through a black neighborhood at night and you don't think he will be asked what he is doing there?--hoodie or no hoodie.