On this site academic social science researchers have the opportunity to comment on the reviews they have received, and the process of decision-making about reviews, affecting articles submitted for publication, book proposals, and funding applications.
So far there seems to be only one submission (by the site’s author) but I can see the potential. The addition of a simple scoring system so that you can rate your experience with certain journals might work even better. The danger is of course that the website becomes just another channel for venting the frustration of rejected authors.
In my opinion, making the reviews public (perhaps after the publication of the article) is the way to go in order to increase the accountability of the review system.