... Notably, we find evidence of an association between ideological affiliation and the technologies, institutions, and practices of participation across political blogs. Sites on the left adopt more participatory technical platforms; are comprised of significantly fewer sole-authored sites; include user blogs; maintain more fluid boundaries between secondary and primary content; include longer narrative and discussion posts; and (among the top half of the blogs in our sample) more often use blogs as platforms for mobilization as well as discursive production.
[O]ur study suggests that the prevailing techniques of domain-based link analysis used to study the political blogosphere to date may have fundamental limitations. The fact that we find evidence of significant cross-ideological variation when we compare intra-domain attributes of political blogs demonstrates that link analysis studies have obscured both the diversity of participatory affordances online as well as the primary mechanisms by which the networked public sphere alters democratic participation relative to the mass mediated public sphere.
So, there you go. Couldn't be clearer.