Google Scholar (GS) has begun an international push today with the addition of content in two languages as well as new interfaces for four countries.
Anurag Acharya, the creator of Google Scholar, told me to expect announcements about additional languages being availble as soon as the database has enough content in a particular language.
You can also change the Google Scholar interface by using the GS preferences page. It's also now possible to limit to Chinese (Simplified), Chinese (Traditional), English, and Portuguese from the preferences page. At this time, a language limit does not appear on the advanced GS interface. Those with interest in other languages might want to monitor this page on a regular basis for new additions.
Finally, I asked Anurag a question (he expected it) that several of my librarian colleagues have asked me since Google Scholar launched. Is a list of the sources Google Scholar indexes covers available? Unfortunately, Acharya told me that no comprehensive, one-stop list is available or in the works.