This is, fairly transparently, just Wikipedia language with Wikipedia removed and Wiktionary inserted in it's place. I am going to rewrite some of it in such a way as to reflect Wiktionary specifics. - TheDaveRoss 22:10, 3 October 2006 (UTC)
Wiktionary's editorial policy is the "neutral point of view", often abbreviated "NPOV". This policy says that we accept all the significant viewpoints on an issue. Instead of simply stating one perspective, we try to present all relevant viewpoints without judging which is correct. Our aim is to be informative, not to convince readers of something.
It's OK to state opinions in articles, but they must be presented as opinions, not as fact. Also, it's a good idea to attribute these opinions, for example "Supporters of this say that..." or "Notable commentator ___ believes that..."
You might hear Wiktionarians referring to an article as "POV". This is Wiktionary slang for a biased article, or one obviously written from a single perspective. Advertising would fall in this category, as would a political diatribe. In a less extreme case, an article might have "POV" problems if it spends significantly more time discussing one view than another, even if each view is presented neutrally.
This policy is reflected by the fact that there is no preference towards one variant of English, and that both US and UK standards are welcome on Wiktionary. Keep this in mind when editing; do not change regionally different spellings simply for the sake of it. It is only justified when done in order to keep a consistent usage througout one article, or to apply that spelling which is most logical for a regional topic (e.g. "World Trade Center", not "World Trade Centre"). If the subject is neutral, the original contributor's usage should be followed.