The good news is that an agreement has been reached on the Sitemaps protocol by Google, MS, and Yahoo! (via TechCrunch). The Google originally developed this protocol.
The bad news is … who’s using it? Supposedly Sitemaps improves ranking, but a quick sample - techcrunch, digg, odeo - found 0 out of 3 using it (404s for site.com/sitemap.xml and site.com/sitemap_index.xml).
Okay, but it’s kind of complex for a custom website to build in support … so maybe it’s down to CMSs to offer built-in sitemap support. Nup. Neither WordPress (according to this blog) nor MediaWiki (according to Wikipedia) support it. There’s a WP plugin, but …
Maybe this agreement will spur the CMS developers to support sitemaps. I’ve never really understood exactly what it offers that robots doesn’t, and I’m hoping the sparse Sitemaps website will illuminate at some stage.