I base my decision solely on the quality of the node, not who wrote it. It does not matter to me if it was written by AM, a registered user, or created by a power surge through the perlmonks.org server. :) Except vroom of course - one should never vote his down. Who knows what will happen when his script kicks in:

if ($vote=-1 and $node->{owner} eq "vroom") {
  &SendToUser($Locusts && $Plagues && $Telemarketers);
  $Users->{XP} -= (rand 50) +50;
}
[download]

But I, too, am less likely to vote on an anon monk post. It has to be really good or bad for me to bother.

To be honest, I don't think any node has ever suffered a fatal accident. A few have quietly passed away under the protection of a DNR signed by the author, but none (that I know of) have been voted into extinction. Which is amazing considering the incredably low reputation of some posts. Of course, the best person to ask would be the regulator himself.