You can now use your robots.txt file to point search engines to your site’s sitemap file. This saves time because you’ll no longer have to register with each search engine and submit your sitemap’s URL. Just update your robots.txt file with the location of the sitemap, and search engines will figure it out for themselves.
Here is the line of code to add to your robots.txt file:
And your robots.txt file should be in your site’s root directory, at www.yourdomain.com/robots.txt
There are still plenty of reasons why you’d want to register with the webmaster services sections of search sites, but this is no longer one of them.