Google Sitemaps is a service to allow webmasters to describe what is changing on a site to make it easier for Google to index. There is an interview with the Google engineer at New “Google Sitemaps” Web Page Feed Program on SearchEngineWatch.
I wonder if wikis could be set up to create the sitemap automatically? This is courtesy of Matt Patey who pointed me to the Slashdot | Google Launches Google Sitemaps post.