[metageek]

>I'm not aware of any broader literature or even editorials describing what value, if any, is added by the current system.

I can just imagine the challenge of getting such studies published.

[chalst]

There are many conferences that deal with open access in the context of scholalrly publication. E.g.,

  http://www.lub.lu.se/ncsc/program.html

Peter Suber keeps a list:

  http://www.lub.lu.se/ncsc/program.html

Many library science journals are open access, e.g., Ariadne. Example article:

  http://www.ariadne.ac.uk/issue57/waaijers-et-al/