i read, some people submit the RSS feed of their wordpress.com blog as a sitemap in goolge webmaster tools. But on googles faq i also read this:
Generally, a syndication feed does not include all URLs, so if you want to use the feed to let Google know about all URLs in your site, you may need to adjust your feed settings. If your feed includes only recent URLs, Google can still use that information to find out about other pages on your site during its normal crawling process by following links inside pages in the feed. If you use this format for your site, simply add the URL of the file.
So does any of you have experience if submitting the feed as sitemap does any good? Or does it even diminish the number of pages google sees on your wordpress.com blog?