The statistics are derived using web, network and server diagnostic tools. Visits reflects how a site rates among all sites on the Web with reference to the number of unique visits. This is based on hit counts recorded from various caches on the Internet backbone. The speed ratings are compiled based on a periodic archival update of the Web. Links In reflects how many other sites are linking in to a domain, which reflects how valuable its resources are considered to be by peer and related sites, portals, etc.
Pages refers to the number of pages, and is a reflection of content.
Sites with a relatively small number of pages can be considered in general to be more marketing-oriented, while sites with many pages reflect a content orientation. Also remember that in addition to the fact that some of these sites are dedicated or largely dedicated to GIS and others are not, that some sites place their mapping or GIS content on a seperate domain, and some do not. Conversely, Microsoft has a unique domain for its relatively new TerraServer, and the number of visits to this unique domain is quite impressive. These ratings will be updated monthly, so do come on back and see us. If you have a site you'd like us to rate, just let us know.