I recently saw this reasonably interesting graphic regarding journals and open access.
As many of you know, there is a large discussion about open access. It appears to be most strong within biological sciences, though that may be more of a side-effect of their style of publishing. An interesting "timeline of open access" unfortunately stops at 2008. Obviously the graphic, while interesting, is a single data point.
What is the evidence regarding the effect of going open-access and a journal's impact factor? I am especially interested in utilizing resources that have undergone some kind of peer review and scrutiny.
A few years ago there appeared a nice article in Science:
The authors convincingly show that going Open Access widens the readership of journals and improves citation counts.
There are some interesting references in that article too.