Find high, medium, and low authorative starting points for an issue with the Technorati scraper and Charts of the (Relative) Actor Resonance Per Issue. Use these starting points as input for co-link analysis with the Issue Crawler. E.g. Bruns' article on using the Issue Crawler and Technorati in Methodologies for Mapping the Political Blogosphere (2007).
Charts of the (Relative) Actor Resonance Per Issue in the Blogosphere. This tool charts the amount of issue postings and the ratio of issue postings to an organization's association with the issue postings.