RSS submission can boost your blog's ranking considerably if the directory, to which you are submitting your blog, is of high PR and high authority. When you submit your blog to any RSS directory, your recent posts are fetched automatically and backlinks are created from those directories whenever you post something new on your blog. So you don't need to do a lot of work for building backlinks for each and individual posts when you submit your blog to some reputable RSS directories.
I have compiled a list of 25 high PR RSS directories which accept free RSS submission. Furthermore, many of these directories even don't ask to register or verify your details, so they don't waste your time and you can submit your blog in no time.
License: Freeware Image Source: IconArchive
Here is the list of these RSS directories. I hope that these sites will surely help you in boosting your blog's ranking in SERPs, as well as will refer some visitors also.
http://www.blogdigger.com/add.jsp PR7
http://www.rss-network.com/submitrss.php PR6
http://www.icerocket.com/c?p=addblog&url= PR6
http://www.blog-directory.org/add-blog.php PR5
http://www.getapodcast.com/AddFeed.aspx PR5
http://www.rssmotron.com/feed_submission.php PR5
http://rsslounge.com/submit PR4
http://www.feedplex.com/add-url.php PR3
http://rssfeedurl.co.cc/submit.php PR3
http://rssfeedurl.co.cc/submit.php PR3
http://anse.de/rdfticker/addchannel.php PR3
http://www.ian-tn.org/submit.php PR2
http://www.allenre.com/submit.php PR2
http://rss.buymyscripts.net/submit.php PR2
http://www.feedmyrss.org/submit.php PR0
http://www.rsslinks.in/submit.php PR0
http://www.rssfeednews.in/submit.php PR0
http://www.whatisrssfeed.com/submit.php PR0
http://www.rssnewsdirectory.com/submit.php PR0
http://submitrss.info/submit.php PR0
http://www.readablog.com/AddFeed.aspx PR0
http://www.rssfeedslinks.com/submit.php PR0
http://www.goldenfeed.com/AddFeed.aspx PR0
http://www.flchili.com/submit.php PR0
http://www.rssaggregator.org/submit.php PR0
http://www.rss-network.com/submitrss.php PR6
http://www.icerocket.com/c?p=addblog&url= PR6
http://www.blog-directory.org/add-blog.php PR5
http://www.getapodcast.com/AddFeed.aspx PR5
http://www.rssmotron.com/feed_submission.php PR5
http://rsslounge.com/submit PR4
http://www.feedplex.com/add-url.php PR3
http://rssfeedurl.co.cc/submit.php PR3
http://rssfeedurl.co.cc/submit.php PR3
http://anse.de/rdfticker/addchannel.php PR3
http://www.ian-tn.org/submit.php PR2
http://www.allenre.com/submit.php PR2
http://rss.buymyscripts.net/submit.php PR2
http://www.feedmyrss.org/submit.php PR0
http://www.rsslinks.in/submit.php PR0
http://www.rssfeednews.in/submit.php PR0
http://www.whatisrssfeed.com/submit.php PR0
http://www.rssnewsdirectory.com/submit.php PR0
http://submitrss.info/submit.php PR0
http://www.readablog.com/AddFeed.aspx PR0
http://www.rssfeedslinks.com/submit.php PR0
http://www.goldenfeed.com/AddFeed.aspx PR0
http://www.flchili.com/submit.php PR0
http://www.rssaggregator.org/submit.php PR0
So go there and submit your blog URL to each of these directories. As second PR update of 2013 is near, so these directories can help you in getting a better PR. Good luck!