Here are some questions to note against “networks of trust”:
How does one increase the value of the persons entering the network (through referrals) over interaction and “training”? How does the network extract (or scale) value from people who are in the network?
Are tit-for-tat too strict as feedback? Should it be tit-for-two-tat or two-tit-for-tat? What is the optimal positive-to-negative ratio? Would it be based on John Gottman’s “Magic Ratio”?
Are modular sub clusters made as “organs” of a bigger network, thus having divergent utilities, trusts and needs? How can overlapping community detection work?
Would small-world, rich-club-like structures, and critical social conduits create trust network power imbalances?
Can reducing connection strength or quantity of a person’s surrounding bonds increase their efficiency? How can it be optimized based on Dunbar’s Numbers?
Here is the rub against PageRank: EigenCenter, bridging centrality and other indices exists for alternative characteristics. All the web needs to do, is simply render the search engine task into a multi-objective optimization problem. Those that are popular vs those that are comparative vs those that are derivative. Attempts at optimizing the three major mode of creative operation (copy, transform, and combine) are hard but more realistic.