How often does the sitemap update?

Hi,

At first glance the WPMU DEV SEO is looking really good. Just a couple of questions:

- How often does the sitemap update? I've tried creating new pages and posts but the sitemap doesn't seem to update (on the main blog in a multisite install) until I visit the WPMU DEV SEO settings page. I haven't been able to get it to update on any subblogs yet.
- I noticed in the plugin files there appears to be references to a video and news sitemap - is this planned functionality or something that is already available?

Thanks in advance.

Cheers