The AnonNews forums are very loosely moderated, in fact very little will be removed - however, there are a few rules.
Content that is harmful towards users is not allowed. That means no posting of malware, phishers, etc. Commercial/promotional content is also not allowed - this includes merchandise and 'content farms' that are obviously designed for turning a profit. Content that carries serious legal liability (such as child porn or fraud) is also not allowed, to protect the AnonNews infrastructure. Discussion about these subjects is allowed, as long as no practical instructions and/or actual content is provided.
Because of legal liability, organizing Anonymous Operations that are based on outright illegal activity - such as LOIC/DDoS operations - should not be organized from these forums. Discussing them is of course allowed, as long as no actual organization takes place (that means no posting of targets and manuals and such). There are plenty of places to organize these kind of operations, look at the Related Sites section for some examples.
Except for the offtopic forum, all threads should have at least some relevancy to (a part of) Anonymous. Discussing things that are not directly related but may be of interest to Anonymous, is of course allowed. Please don't post 'how do I hack' topics anywhere, for those kinds of things there are sites like HackForums.
While there is no real moderation on this, you are encouraged to post topics in the 'appropriate' categories - this will ensure that those interested in the subject will read them. This is not a real "rule", topics will not be moved when placed in the wrong section.