George Zimmerman should be forgiven. While what he did was disgusting and terrible, he should be forgiven because that is the moral thing to do. Forgiving some one also occasionally gives the victim's family some closure about the whole situation, and I believe that is what is needed in the Martin case.
Have you ever heard the phrase "Forgive and forget"? That applies to everyone. You can't forget what someone did before you forgive them from your heart.
"Be kind and compassionate to one another, forgiving each other, just as is Christ God forgave you,"
He should be forgiven unconditionally, but only allowed to go home if he agrees to take a solemn oath never to commit second-rate murder and apologize sincerely to Martin's parents.