Which major search engines support the Google Sitemaps Protocol?

Although Google dominates search, I'd like to get the most out of my efforts to create and maintain a Google Sitemap. Are there other search engines which accept mass URL submissions via XML sitemaps? Yes.

Google Sitemaps KB · Index · Expand · Web Feed

Google Sitemaps for (tens of) thousands sub-domains

Which URLs should I put in my Google Sitemap?

At the time of writing this piece I'm not aware of other engines supporting Google's Sitemap Protocol. At least not officially. Actually that's a shame, since Google made the sitemaps technology open source, and encouraged other engines to participate.

However, the good news is, that MSN and Yahoo both accept mass URL submissions. Yahoo started to process submitted URL lists in plain text format shortly after Google's Sitemaps announcement, and added support of RSS, ATOM, and HTML sitemaps a few months later (details). MSN keeps a very low profile, but silently has started to process XML sitemaps. At least they extract URLs from XML files in general, and crawl those. Both Yahoo and MSN don't tell whether they revisit sitemaps, so it's a good idea to resubmit them every once in a while.

As long as Yahoo doesn't accept XML sitemaps, you should use a sitemap generator which can output text files or feeds, for example GSitemapCrawler or SimpleSitemaps.

Update: Yahoo and Microsoft support XML sitemaps. For more information refer to sitemaps.org