danah boyd's The Biases of Links, seems to be a point of coalescence for a number of issues I occasionally snipe at: network structure in the blogosphere, blog crawling, aggregator design, etc. etc. Someone should really follow up on her informal analysis with a little more rigor to see if the patterns bear out.
Pondering Calacanis' challenge and Finkelstein's musings, I realized there's a certain flaw with Technorati's authority lists. As far as I can tell, they actually don't serve any purpose other than promotion. A close read of the original Google search engine paper indicates that PageRank was developed specifically to support improved relevance based upon traditional IR techniques. PageRank has a specific purpose in life.
If Technorati authority is supposed to help their keyword search, I'm missing the connection. Authority is "just" a promotional vehicle. If you want to reach people and influence minds then that has a lot of value if a lot of folks pay attention. In some sense, spending money to improve the rankings has to be balanced against promoting Technorati's corporate visibility.
Since I'm not as invested in the politics of the blogosphere as others (no blogroll, no comments, no trackback), what's my angle? Well, if aggregators are going to morph, they need good metadata about information ecologies, cleanly exposed. Mary Hodder and friends took a stab at cooking up a new ranking system, which is fraught with all sorts of issues (lots of noisy inputs, some quite hard to get, complex remixing) but thinking about engines that support such ideas is a wide open area of research.