Optional. See Slash::Tools::CONFIG.
Previously, any tag on a comment in the hose _other_ than nod would effectively remove it from the editor's view of the hose. Now, only 'nod' and 'nix' do that.
A more accurate way of tracking is_spam and Despam changes in the firehose, and now adminmail reports 3 numbers for that instead of 2. And more debug logging for Slash::Clout::Vote peer clout calculations.