Argentina Forcing Google & Yahoo To Censor Search Results from Search Engine Land covers this very well. In short, Argentina is forcing, by court order, Yahoo and Google to censor their search results. The results being censored are for select public officials, models, actors, and sports stars.

For example, a search on popular soccer player, Diego Maradona returns no results at all and a message that means:

Here is a screen capture:

Why do results come up at Google? Well, Google is censoring the results, but not completely removing the results like Yahoo.

We have discussion on this topic at Sphinn where one member seems to really know a thing or two on the topic. He said:

Under the laws of which they run in that specific country. That is how it works.

Forum discussion at Sphinn.