Games Workshop, rightfully so, is very protective of it's intellectual property. Do not, under any circumstances, reproduce or quote anything directly out of a Games Workshop publication.
It's OK to discuss things but here are some things I never, ever want to see:
ONLY ever post a unit stat-line in its entirety if it is your OWN unit that you have created. It is OK to discuss or mention elements of GW statlines related to a discussion but never the whole line.
Never directly quote out of a Games Workshop publication. If it's essential that the exact wording be seen by those participating in the discussion give it's page number and location on the page.
Never give another person a full description of what a magic item does, even if you paraphrase and don't directly quote. Games Workshop doesn't want freeloaders getting the rules without getting the book and neither do I.
Never reproduce, even in part, an article from a Games Workshop publication of any kind including White Dwarf or any of Games Workshop's online publications. It's OK to discuss them and paraphrase parts of them that relate to a discussion.
The main reason for these rules is that Games Workshop, myself, and anyone who respects the game does not want unscrupulous individuals who do not want to buy a proper army book to get the rules.
Also do not:
Do not Discriminate against others
Publish, post, distribute, or otherwise disseminate content that is libellous, defamatory, that invades privacy, or is obscene, pornographic, abusive, harassing, or otherwise unlawful or objectionable or which infringes on any intellectual property or other rights of any entity or person
Threaten, harass, stalk, abuse others, or otherwise cause distress or unwanted attention to any person
Upload files that contain a virus or corrupted data
Engage in any unlawful purpose, or use this site in a manner that is contrary to any law or regulation
Promote or encourage any illegal activity
Interfere with this site's availability to other users
Transmit advertising, promotional materials, chain letters, pyramid schemes, or make any commercial use of this site