tedster - 9:21 pm on Mar 12, 2010 (gmt 0)
Google's John Mueller (JohnMu) has written a short article for the official Webmaster Central blog on the often frustrating topic of Multi-Region websites. The summary covers a lot that members have mentioned here - that the strongest geo-targeting signals come from a ccTLD (country-code Top Level Domain), then from the server location, and then from "other signals".
I appreciated the chart he created that summarizes three different ways to use a gTLD (generic Top Level Domain) -- subdomains, subdirectories and query strong parameters in the URL.
The first three elements used for geotargeting are strongly tied to the server and to the URLs used. It's difficult to determine geotargeting on a page by page basis, so it makes sense to consider using a URL structure that makes it easy to segment parts of the website for geotargeting.