I'm not really sure if this is the right place for the language discussion. I believe that everybody on this list at least understands English good enough to be able to get the message and understand the English announcements. Why would someone subscribe to a list she can't follow? And those who will participate in the discussion at least write English well enough to get their message across. Those people don't need translated announcements. In my opinion it is a better idea to post a "request for comment" on each translated announcement page and see how demand is.
I think as a system administrator, one is out of luck if one can't follow the English announcements anyway. I am not an administrator but still I often have to work my way through man pages or HOW-TO's that are not (yet/necessarily) available in my mother tongue. I assume that this is getting more if one is doing this on a professional basis. If one is not a system administrator and one cannot follow the English announcements (How many people are that anyway?) one can probably wait a couple of hours or even days for the announcement to appear in their language on the website. And if timing is really such a big issue, a generic email warning, saying that an issue has been discovered, where the English announcement can be found and where and/or when the translate announcement will appear on a webpage, would suffice. Don't get me wrong. I really appreciate the high level of commitment in the community, but there are probably places where those resources could be better used. If there are people available that can translate the email, then these people can instead translate the announcement and place it on the webpage.