I really think that PR and Marketing is becoming more intertwined these days. More and more I think companies are using social media to connect with their audiences - which include customers, prospects and the media. And more and more those audiences are blurring. I know for us at HubSpot the process of PR and Marketing are very mixed - and this is because of the emergence of social media where you can reach media and customers at the same time in similar ways - and sometimes they are even the same people.
I do think that social media has a really important role to play in PR. It is a great tool to more easily connect with a larger number of people. I can already tell you that I am interacting in a more productive way with more influential people in our industry during my job at PremierMap than I have in previous jobs; PremierMap is only a small company with a long history. Old school media has made this possible.
I also think social media has a really important role to play in marketing. We use all forms of social media to market Premiermap (Facebook, Twitter, LinkedIn, Blogging, Digg, Delicious, etc.) and they have been very effective.
But, as I mentioned earlier, it is hard to separate them. The people I interact with are often both potential customer and media member. After all, pretty much anyone with a blog or even a Facebook account is a member of the media today, since even with a tool like Facebook you are publishing content to your readers (friends).
