Google provides more information about the URL Parameters feature in Webmaster Tools designed for webmasters who want to help Google crawl their site more efficiently. Maile Ohye explains the
configuration parameters in a video. By telling Google how parameters behave and the recommended action for Googlebot, webmasters can improve your site's crawl efficiency. If configured
incorrectly, webmasters may accidentally recommend that Google ignore important pages.
Read the whole story at Google Webmaster Central »