Directory submissions have long been a tool for site promotion. About a year or so ago, search engines began to downgrade directory links and the effectiveness of directory submissions as a tool for building keyword targeted links took a major hit.
As bloggers, directory submissions do still offer a chance to build links albeit largely weak links, and some would argue whether there were any value in spending time to build links in this way for decreased return. However, feed syndication directories which accept RSS feeds do still offer a good means of building links to your blog content.
Here, I offer a list of RSS feed directories that accept free RSS feeds.
http://www.weblogalot.com/Ping/ – you can also add this to your ping list for automatic update.
http://rssmountain.com/submit_anonym.php
http://www.rssmicro.com/feedsubmit.web
http://www.feedage.com/ (requires free login)