Legally, I'm pretty sure the Gabe & Tycho were totally in the right. The comic was pure parody, which is strongly protected. But they were also right to pull the comic instead of fighting, because there is no way they could have afforded the legal fees.
This is why we need the English Rule in American courts, where the loser has to pay the legal fees of the winner. Then Gabe & Tycho could probably have hired somebody to defend them.