If you been using google sitemaps for some time , you might know about this , Google Sitemaps has been rename to Google Webmaster Tools, Check out Google Webmaster Central ( sitemaps is included ) for your sitemap status.
I just found out that my sitemaps is not working for some time , trying to debug now, during playing with the setting, one of the new feature that i think is great you can set preferred domain URL format , which mean you prefer google index your site with or without www( i hope this can help me solve my page rank dropping issue after switch to no-www )
