Here is great news for webmasters who were confused on how to use sitemaps for different search engines.
Now GOOGLE, YAHOO, MSN and ASK have unified to provide a solution for this.
To enable these search engines to auto discover your sitemap you just have to provide the path of sitemap in your robots.txt file.
Eg – Sitemap: http://www.yoursitename.com/sitemap.xml
Just add this simple line of code in your robots.txt and search engines would auto discover your sitemap.
This would be the easiest way for webmasters to make sure that all their pages are properly and timely spidered by search engines.
Sooner or later this would surely be followed by all other smaller search engines also.