The policy regarding comments on this site is really quite simple; just behave respectfully towards the people commenting on the site, even if you don't necessarily agree with them.
Any comment containing advertising or spam will be deleted. Personal attacks will be deleted, and most likely also result in the poster being blocked from commenting in the future. Do try to keep a civil tone as far as possible.
Posts containing links may have to be manually approved, and can take some time to show up on the site.
Do not post copyrighted material from third-parties, or link to any form of illegal content.