XML sitemap auto-discovery

Vanessa Fox makes the news: In addition to sitemap submissions you can add this line to your robots.txt file:

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

Google, Yahoo, MSN and Ask (new on board) then should fetch and parse the XML sitemap automatically. Next week or so the cool robots.txt validator will get an update too.

Question: Is XML Sitemap Autodiscovery for Everyone?

Update:
More info here.

Q: Does it work by user-agent?
A: Yes, add all sitemaps to robots.txt, then disallow by engine.

Q: Must I fix canonical issues before I use sitemap autodiscovery?
A: Yes, 301-redirect everything to your canonical server name, and choose a preferred domain at Webmaster Central.

Q: Can I submit all supported sitemap formats via robots.txt?
A: Yes, everything goes. XML, RSS, ATOM, plain text, Gzipped ...

Tags: Search Engine Optimization (SEO) Google Sitemaps robots.txt Yahoo MSN Ask