I would say Planet13 that carefully assessing ranking positions on select content websites, web 2.0 sites, and creating a rolling "site id" can help us understand
a) What websites are out there for each "bucket" or function
b) Can be based on pagerank, but better to be based on age, size of website, inbound links and of course ranking of pages
c) The list can be changed over time. This way if one of the websites (ie Squidoo) were to take some kind of demotion, your next month plan would no longer involve them.
I do this type of rolling understanding of potential hubs alot.