While I agree with Jeff that, considering the target audience, international versions of Stack Overflow and ServerFault wouldn't make much sense, I do think they would be great for Super User.
I'm German and I know a lot of people who would love to use this site but can't since their English isn't very good or just wouldn't want to bother with it.
The whole "English is the definite language"-thing doesn't hold up to general computer use.
Regarding automated translation: I haven't seen it done in a way that made much sense but I would love to stand corrected.
Edit: Actually even for Stack Overflow and ServerFault translations might be a good idea. Attach a "translate" button to the question and the accepted answer.
Anyone with a rep > x can translate it, and anyone with a rep > y can vote up the translation. A translation with more than z votes becomes the "offcial" translation and the translator gets some rep from it.
The official translations can be found by on-site searches and search engines.
I know I would translate questions that helped me or I found intresting to German.