Lilia Efimova has a dissenting opinion in the "my weblog is my social software" meme: “Learning about someone from a weblog takes time. Personality appears in a context and through time to read many lines of weblog posts and to participate in conversations. And it's even more difficult to learn about someone's network: linking, blogrolls and RSS subscription lists tell a bit, but you never know if linking or blogrolling means regular reading and how many e-mails/IMs/calls were exchanged next to blogging.”
Social network software, Lilia argues on the other hand, shows fuzzy relationships to people, but at least it shows them now.