Some people might find that certain MediaWiki sites such as Metapedia,
Encyclopedia Dramatica or even certain parts of Wikipedia offend their moral
standards. But there's not much that we can do about that. If MediaWiki were
proprietary software, the organization owning the copyright could refuse to
allow certain entities to use it. But the MediaWiki community is rather
powerless to influence how people use the software, because the licensing
allows it to be used for any use. Even if we built in code to enforce some
standard of morality (e.g. installing porn filters similar to Google; see
http://en.wikipedia.org/wiki/Safesearch), anyone would have the legal right
to remove the filters and to distribute the modified code, or to create a
patch to disable the filters. Therefore, morality is mostly outside the
purview of the MediaWiki community. On the other hand, if someone wanted to
put Extension:PornDistributor on
MediaWiki.org, or if someone wanted to link
to Pornopedia from
http://www.mediawiki.org/wiki/Sites_using_MediaWiki/en, I
guess disputes about morality could occur, but so far that doesn't seem to
have happened.
I think the best thing for those who are offended by certain content to do
is to improve code such as
http://www.mediawiki.org/wiki/Extension:ImageFilter so that it will be more
feasible to create mirrors of various wikis that allow users to opt out of
viewing content tagged as adult, sacrilegious, immoral, or whatnot. The
openness of the software and the content is beneficial in that it allows
people to tweak it as needed to suit their tastes. Then of course there is
always the possibility of buying third-party web-filtering software.