I thought this might be of interest to somebody.
Unfortunately for many, one can't post to many of these unless one has had something published (a letter to the editor that is listed in PubMed can suffice).
NATURE NEWS BLOG
The new dilemma of online peer review: too many places to post?
14 Mar 2014
Posted by Richard Van Noorden
http://blogs.nature.com/news/2014/0...line-peer-review-too-many-places-to-post.html
Unfortunately for many, one can't post to many of these unless one has had something published (a letter to the editor that is listed in PubMed can suffice).