Canon is another word for official. It is mostly used to differentiate between the official storyline in which the fan fiction is based on.
The White Wolf canon is generally defined as all official game books released by White Wolf Publishing. The various "official" references (such as the novels) may be used as a guide to canon information, but are not necessarily canon in and of themselves. The Kindred: The Embraced TV series and the computer/console games are not strictly considered canon (although the relevant material is still considered appropriate for posting on this Wiki), nor are fan works.
The definition of White Wolf canon may vary for different fans, and therefore for a reference source like the WWWiki, the question may become especially difficult.