There is no reason why MediaWiki can't become
multilingual. Since this has
not happened on its own (probably due to the use of subdomains) we could use
some of our award money to put a bounty on that. Somebody already tried to
submit a patch for this
... which was woefully incomplete. I am completely in favor of properly
internationalizing MediaWiki and putting a bounty on the implementation.
However, such an implementation should be generic, i.e. it should allow us
to migrate Wikipedia itself into that system. This requires some way to
deal with namespace conflicts - e.g. wikimedia.org/en/Merchandising
(the current Merchandising page on Meta is
actually German), and we would have to set up automatic redirects for
subdomain access. Given that, setting subdomains up now while we don't
have this advanced code will put us well on the road to a nice general
solution for all Wikimedia projects once we have it.