For anyone (like me) who raised an eyebrow at the "trans fats are highly toxic" bit, wiki helpfully mentions some recent (2013) FDA guidance on the matter: http://en.wikipedia.org/wiki/Trans_fat
Calling "Wikipedia" simply "wiki" is like saying "book mentions..." when talking about what a specific book discusses.
I have seen this usage become increasingly common, but I try to discourage it when I see it, because it does cause confusion, and if it catches on, could cause even more when trying to discuss other wikis as people may assume that you are talking about other Wikipedia affiliated sites, not other instances of the general category of wikis.
Do not let the word wiki in its name and the content being provided by users through a wiki engine fool you, wikipedia is not a wiki (for a variety of reasons) but this is a common misconception.
Let's just say that if openstreetmap had been called wikistreetmap and used a wiki engine, it would still be "a map of the world, created by people like you and free to use under an open license." and not a wiki.
So yes using wiki as a shorthand to refer to wikipedia is not only confusing but also wrong.
[1] : http://c2.com/cgi/wiki the original wiki
-edit- meatball[2] is a wiki, consumerium[3] is a wiki everything2[4] is not a wiki[5] and everything2 not being wikipedia[6] doesn't make wikipedia a wiki.
[2]: http://meatballwiki.org/wiki/ [3]: http://develop.consumerium.org/wiki/Main_Page [4]: http://www.everything2.com/ [5]: http://everything2.com/title/wiki [6]: http://www.everything2.com/title/Everything2%20is%20not%20Wi...
You are free to complain about or dislike that, and to want people to broaden their horizons if they think of it as the wiki or as the default thing that "wiki" refers to, but you are not free to claim that most people, when they say "wiki" as a shorthand for a site, actually mean some other site, or that some other site which could be called "wiki" is more likely to be meant.