The funny thing about using social media for PR, is that we sometimes end up caught between two opposing paradigms.
Generally speaking, writers/reporters/editors would prefer if PR were an invisible part of the process. At the end of the day, we're all working to ensure that the final written product appears to be the journalist's, rather than the publicist's, creation.
Social media, on the other hand, works in the opposite way. The network itself finds a way to encourage views of content it deems to be useful, relevant or interesting - for whatever reason. Information - oftentimes supplied by a publicist - gets retweeted, dugg, shared on facebook and myspace, and otherwise moved up the chain of online relevance. The content of the article is what matters - not necessarily the source.
Which is exactly why using social media for PR purposes is so refreshing. Anyone - a non-profit organization, a consumer products company, or a publicity firm - can circulate information online. The only requirements are that: