I often tell my students to beware of Wikipedia and wikis and that if they are going to use a wiki as a source of information, to make sure that it can be backed up by at least two other separate sources. I would only recommend TFwiki as a final resort - i.e. if you cannot find the information anywhere else, and I will admit that TFwiki does contain some information which cannot be easily found anywhere else and it's good for that. But overall I am very unimpressed with it as a TF resource.
That is good advice and not just for the TF wiki but wikis in general. They are afterall public edited articles and as a result each has their own quirks, attitudes and culture just like any other community. I have found that wikis are only good for absolute 'Black or white' facts such as 'When was such a toy released' or 'What date did WWII end', stuff like that. Anything that requires opinion or observation of sorts I cross reference unless they have included a concrete third party source stated in the article.