Google and their Sitemap
The Google Sitemap system just turned one year old! The “Big Daddy” infrastructure and the “Crawl Caching Proxy” look like they were made to be a perfect match for Google Sitemaps (but it is more likely the other way around). In theory, Google Sitemaps can tell the Google crawlers more about a website, even without having to crawl it. The attributes can be used to help the proxy determine when actual accesses are necessary, keeping bandwidth use on all sides at a minimum.