1. Negative comments about something that has been posted are not LR. If someone would reveal something persona about a poster that would be.
2. Asking someone to prove his humanity in order to log in is onaat devarim (@mods).
3. Negative articles about individuals or groups may or may not be LR. In many cases the tzibbor should be warned about them. If someone is a rasha it is a mitzva to condemn his actions.
