I was looking for a way to publish my blog updates out to all of my social networks all at the same time. WordPress.com offers the Publicize option inherently, but it only works with Twitter, Facebook and Yahoo. I have used Ping.fm for a couple of years to manage all of my updates to Twitter, Facebook, etc. Now I see that they also support posting via an RSS feed. Hopefully this works out well, as it will solve the social network updating for my blog.