Walking away is never childish. He is being the bigger man. If he lashed back, he would get himself in some sort of trouble. Maybe a warning or a banning, who knows. But, if it were you, nothing would become of the situation.
Actually Maple, walking away would mean that he walked away and didn't say anything about it. But rather, he had to make this dramatic post that this would be his last post and to his friends he love......BLAAAH. To be honest, we could careless, if your walking away from the site then do so without telling. So, he was no bigger man.
Anyway....back on topic.
Fighting is cowardly and shows weakness. He did the right thing. He doesn't have to leave the boards but walking away from the argument is the right thing to do.
I haven't had the chance to ride the Raven or GhostRider.
Man, I'd report you for this flame but nothing would be done.