Great work - easy to integrate and use. I am using it in both of my two projects. It works as expected and provides beside the user-readable sitemap also an xml-sitemap for our good friends - the search-engine bots. The periodically refreshed content will always provide the latest content available.

One thing might be nice to have in future:
In the module settings of a menu one can choose to start displaying the menu's hierarchy from a specified level on. It really would be great, when XMap would adhere to this setting.
That would improve the narrow shaped hierarchy-structure of Joomla enormously. With this a site admin could structure his site deeper and needn't to have any fears of showing a sitemap - because all menu items that should not be visible won't be shown at all.

This one is quite better than NotifyAdmin I used before. It has various possibilities to get a notification E-Mail. Especially for Sites where many users act as authors, etc. it is necessary to track all changes regarding articles.

I'm looking forward to see this plugin growing!