Except to the degree that it raises barriers to publication for
authors -- which, of course, it does.
Except, of course, where there are no author fees (in the case of
over half of the journals listed in the DOAJ), or where the
authors fees can be waived (BMC, PLoS, etc.).
(Incidentally, I always find it intriguing that open access
publication fees are described as barriers to publication, but we
rarely hear the same being said of page charges, colour figure
charges, etc. for publication-based journals.)
David C Prosser PhD
Director
SPARC Europe
E-mail: david.prosser@bodley.ox.ac.uk