Hello,
I'm using your plug-in on Orchard 1.7RC on my site. I can access the sitemap.xml from a browser, but when I use Fiddler to ping it, or try to hit any other sitemap validating service, it returns a 200OK with no payload.
You can try it for yourself at http://advancedrei.com/sitemap.xml.
Any ideas?
Thanks!
-Robert McLaws