Remember, broadly speaking, defamation is just undertaking some action that gives some entity a negative image. Before you go nuts on that, yes, truth is a defense against defamation (ie: it is not defamation if it is true). At which point parody becomes defamation is something of a grey line, which Carreon will try his hardest to use.

If Carreon can paint the image in court that the internet is after him, it would probably help him make his case that the fake twitter account is defamation, not mere parody. After all, context matters.

He's decided to blindly start swinging. While it is certainly possible that he will not hit anything regardless of the community reaction, the minimal probability of success will be such a pain-in-the-ass that it is not worth it.

Of course, the mob's lust for blood achieves nothing but self preservation, and even if the claims are baseless, we're observing each day the consequences of its actions; mostly in the form of Carreon building up his case with ostensibly supportive evidence, and dragging other websites into the fray who had no involvement except to allow people to comment.

But, I dunno, I'm not the greatest advocate of internet vigilantism.

  >  If hundreds of assholes and a dozen criminals support
  > you, then that makes it seem more likely that you are
  > an asshole or a criminal.

I'm not sure why you feel this is the case. They've been careful to redact Carreon's contact info from the document's they've published and they've been saying things like "And to anyone else who is reading this: it goes without saying, but stop harassing Carreon. Be lawful and civil in your interactions with him."

I don't believe at all that that's Inman's intent.

1. http://theoatmeal.com/blog/funnyjunk 2. http://theoatmeal.com/blog/funnyjunk2 3. http://theoatmeal.com/blog/funnyjunk_letter