I have just seen Jeffrey Beall's "analysis" of MDPI http://scholarlyoa.com/2014/02/18/chinese-publishner-mdpi-added-to-list-of-questionable-publishers/#more-3072 and wish to respond immediately.
I will not respond to all Beall's criticisms.
Beall has set up a site where he lists questionable (aka predatory) Open Access publishers who have poor or non-existent quality controls or have questionable organisations. This is potentially a useful service, though it is inappropriate that it should be done by a single person, especially one lacking discipline knowledge.
I have no personal involvement with MDPI. I remember when they started as a company which actually took physical chemical samples and stored them so that people could check later (the acronym MDPI can also stand for Molecular Diversity Preservation International). The compounds were linked to a journal, "Molecules" with full text. It has been going for 17 years. At one stage I wrote to them and asked them to change the licence from CC-NC to CC-BY and they immediately did.
I have never had any reason to doubt the validity of Molecules. I am now using it as an Open Access source of material to data-mine. We are doing the same with "Materials" and "Metabolites".
Beall's criticism that these are "one-word" titles is ridiculous and incompetent. They are accurate titles.
I have read (as a human) hundreds of articles in these publications. If I were to review a paper in any of them I would assume it was a reasonably competent, relatively boring, moderately useful contribution to science. The backbone of knowledge. I would expect to find errors, as I would in any paper. I reported one in my last post. This wasn't fraud, it was a product of the awful state of ALL scholarly publishing where paper processes breed errors.
It is right that there should be a list of irresponsible journals and publishers. It should be run by an Open organisation, not Beall. Maybe OASPA? Maybe SPARC? I don't know. It is wrong that a single person can destroy a publisher's reputation.
It is also right that we should highlight the equally awful (if not worse) practices of closed access publishers. Why is there no organisation campaigning for reader rights? It seems to fall to me, an individual.
All publishers have junk articles and fraudulent articles. We don't know the scale. (It's a pity that they publishers so little to enable technical solutions to this). By default I would say that a paper in Molecules is no more or less likely to be questionable than one in a closed access journal from Elsevier or ACS.
The main problem is that the Open Access community has failed to get its act together. And that the closed access community prevents anyone getting an act together.