I miss the sense of ocmmunity we used to have in PR blogosphere. When I first started blogging there were only a handful of PR blogs and it was possible to read all of them. As our numbers swelled, Constantin Bastura created a Blogdigger Group of all the PR blogs that he knew of. It was great, the most recent entries floated to the top, so you had a sense of the PR zeigeist. You could so a search on a topic so you could see what your fellow PR bloggers were saying about it.
There was also a PubSub listing of top PR blogs, which created a lot of competition in both good and bad ways.
Now there is the Advertising Age list of Marketing Communications blogs. It is useful for research purposes, but does not build community the way the old Bloggdigger list did. The closest thing we have to community nowadays is the For Immediate Release FriendFeed Room. Pleasant, informative, but not the same.