As many of you know, a site map is a standard that describes the pages on your web site.  This standard is now supported by the major search engines (Google, MSN, Yahoo) and is a great way to ensure that all of your content gets indexed without completely relying on your internal linking architecture.  

Until today, these site maps needed to be submitted to the search engines – manually or automatically.   On Google’s blog, Vanessa Fox announced that Google will now “auto discover” your site map file if they are included in your robots.txt file.  It seems that the other search engines will also follow suit.

All you need to do is add a line like the following into your robots.txt file and the various search engine spiders will index the file correctly:

Sitemap: http://www.mysite.com/sitemap.xml

This is great new functionality and nice to see that all of the search engines are starting to adopt these sorts of standards.