I notice the seagull paper is linked in:

A similar pattern appears when algorithms intended to make optimized selections over vast sets of candidates are applied on implicitly or explicitly social systems. As long as the fundamental assumption that the proxy co-occurs with the desired property holds, the algorithm performs as intended, yielding results that to the untrained eye look like ‘magic’. Google’s PageRank, in its original incarnation, aiming to optimize for page quality, does so indirectly, by data mining the link structure of the web. As the web has grown, such algorithms, and their scalability characteristics, have helped search engines dominate navigation on the web over previously dominant human-curated directories. (emphasis added)

Is this intended?