The very word ‘authority’ shares roots with ‘authorship’. The two concepts are indelibly intertwined, linked, symbiotic.
Perhaps then Google’s move toward authorship, identities, and eventually, author rank isn’t surprising. Google’s end game is to go beyond websites, and start indexing and ranking people – or at least their work.
Google Authorship, or rel=author, ties a Google+ account to a piece of content, centralizing a person’s work and allowing Google to associate all that content with a single author (or at least the content the author chooses to claim). In short, it allows Google to identify an author. There are numerous benefits to Google Authorship, but perhaps one of the the most important is the potential implementation of Author Rank.
Author Rank (patented under Agent Rank) would allow Google to rank certain identities (agents or authors) higher in relevant search results based upon algorithmically perceived authority. Google would have an entirely new signal for their algorithm – and a potentially strong signal, at that.