Last year (November, 2006) kichus posted Google, Live and Yahoo were joining hands together to support the Sitemap Protocol on a jointly-maintained site sitemaps.org. Today they moved one step further, joined with Ask in supporting the same and they made the sitemap auto-discoverable. This eliminates the need of submitting sitemaps to each search engine separately. You can do that just by adding a simgle line of code into your Robots.txt. You can read about their announcement here: Google, Ask, Yahoo and Microsoft.
How I can make my Sitemap Auto-Discoverable?
Simply add the following line into your Robots.txt file:
Example: Sitemap: http://www.virtueseo.com/seo-blog/sitemap.xml
Another way of submitting Sitemap to Ask.com
You can also submit to Ask.com just by pinging them using the following URL.
Yahoo! continues accepting Sitemap submissions
You can still submit your sitemap here to Yahoo!, https://siteexplorer.search.yahoo.com/submit. You can simply put your sitemap link there and say submit. Also you can make use of there ‘My Sites’ option under Site Explorer, which will provide more information about what they are doing with your Sitemap.
Google Sitemap (Webmaster Central tool) will continue its support
A Word from the Author:
I am not sure how far this co-ordination will move further from here. Live and Ask are still taking time to come up with anything on this as a user experience.