I found a post by Lorelle that on how to use your RSS feed as the XML for Google sitemaps. http://lorelle.wordpress.com/2005/09/14/submitting-your-sitemap-and-feeds-to-google-blog-search-and-site-submission/
What is still missing is how to verify yourself as the owner of the site so that you can get access to the Google Sitemaps statistics pages.
They offer two methods for how to verify yourself as the owner of the web site. You can either upload an HTML file with a name we specify, or you can add a META tag to your site's index file.
Once you have verified yourself as the owner of the site, the Sitemaps statistics pages give you information such as:
* Top search queries - list the top queries that return results from your site. Note that this list is unrelated to where your site is listed in the search results.
* Top search query clicks - the top search queries that directed traffic to your site. These are the top searches that caused users to click on a link to your site.
* Your pages in Google - the distribution of your crawled pages that are successfully crawled vs. the pages we tried to crawl but couldn't (because of a restriction or error). For details on pages we couldn't crawl, click the link for the error in the Status column.
* The PageRank of your pages in Google - the PageRank distribution of your crawled pages compared to all the pages in Google's index. Our webmaster guidelines provide more information about PageRank. This distribution is for all pages in your site, so the overall averages may be different than the PageRank of your home page.
* Your page with the highest PageRank - the page on your site with the highest PagRank (by month).
* Type - the content type of your crawled pages. We use content type for the File Format search option in our Advanced Search.
* Encodings - the encoding used by your crawled pages.
* Common words - words in your site's content, and in external anchors to your site.