Technorati has introduced a new tool that should prove indispensable to public relations professionals and others interested in identifying the opinion leading conversations within a specific professional community.

In State of the Blogosphere, February 2006 Part 2: Beyond Search , David Sifry introduces us to the concept of the “Magic Middle” of the attention curve. Technorati currently counts about 155,000 people among the Magic Middle, which Sifry defines as bloggers who have 20-1000 other people linking to them. Sifry says that the Magic Middle contains “some of the most interesting and influential bloggers and publishers that are often writing about topics that are topical or niche … – these are blogs that are interesting, topical, and influential, and in some cases are radically changing the economics of trade publishing.”

Technorati’s new Explore tool uses these Magic Middle bloggers to point to the leading edge of the online conversations among communities of interest.

Given that there’s a lot of interesting topical posts by influential or authoritative bloggers in those topic areas, we formulated an idea: Why not use these authoritative bloggers as a new kind of editorial board? Watch what they do, what they post about, and what they link to as input to a new kind of display – a piece of media that showed you the most interesting posts and conversations that related to a topic area, like food, or technology, or politics, or PR. The idea is to use the bloggers that know the most about an area or topic to help spot the interesting trends that may never hit the “A-list”. We call this new section Explore…

These middle tier blogs also define communities of interest in the blogosphere. Its easy to think of the blogosphere as a cacophony of voices spread out over a big long tail distribution. But Blog Finder and Explore help resolve these thousands of blogs into topical, relevant communities of interest that interlink, refer to one another and often wrestle with ideas, discuss them and move them along. People often ask, “what blogs should I read?” And often times a good answer is, “you should read the posts from the leading blogs in topics that of interest you. Blog Finder and Explore make this possible for the first time on a wide variety of topics…

My test search of the top 20 posts in the Explore: pr category yielded a list that included posts by Steve Rubel, Scott Baradell, Phil Gomes, Lee Odden, Josh Hallett and Jeff Jarvis.

Technorati Explore strikes me as a very useful tool that will enable PR professionals to focus in on the discussion in our community.