Google recently released its list of the top 1,000 sites on the web.
The sites are ranked in terms of unique viewers, based on data gathered by DoubleClick Ad Planner. Google explains how this advertising service determines a website’s weight: “DoubleClick Ad Planner combines information from a variety of sources including anonymized, aggregated Google Toolbar data from users who have opted in to enhanced features, publisher opt-in anonymous Google Analytics data, opt-in external consumer panel data, and other third-party market research.”
The top 1,000 list is far from definitive, though. Google has left off specific kinds of websites, such as “adult sites, ad networks, domains that don’t have publicly visible content or don’t load properly, and certain Google sites.” So if you’re wondering why Google.com, for example, doesn’t appear anywhere on the list, that’s why.