As a webmaster, you can control how this feature works by adjusting your Geographic Targeting settings. Log in to Webmaster Tools and choose Site configuration > Settings > Geographic Target. From here you can associate a particular country/region with your site. These settings will determine the name that appears as a region tag. You can learn more about using the Geographic Target tool in a prior blog post and in our Help Center.

We currently show region tags only for certain domains such as .com and .net where the location information would otherwise be unclear. We don't show region tags for results on domains like .br for Brazil, because the location is already implied by the green URL line in our default display. In addition, we only display region tags when the region supplied by the site owner is different from the domain where the search was entered. For example, if you do a search from the Singapore Google domain (google.com.sg), we won't show you region tags for all the websites webmasters have targeted to Singapore because we'd end up tagging too many results, and the tag is really most relevant for foreign regions. For the initial release, we anticipate roughly 1% of search results pages will include webpages with a region tag.