A Black Hat World forum thread asks if Google's algorithms work the same in all the various countries throughout the world.
The quick answer is no, they do not all work the same.
Specific examples include the Google Panda algorithm that launched initially for English language Google engines in February 2011. Then 17 months later, Google pushed it out in Korea and Japan to target Asian languages.
While the Google Penguin algorithm was more global, impacting sites in any language.
Why the difference? Well, if the algorithm is around language and content, then different languages require different algorithms or support for those languages. When the algorithm is more about off-page factors such as links, then language is less of an issue.
Then you have algorithms like spam algorithm aka Payday Loan algorithm that target specific niches and not countries.
So the long answer is that some of Google's algorithms are global on day one, some are for specific countries, some are for specific for niches, some are rolled out slowly to other countries, regions and languages.
Forum discussion at Black Hat World.