Today’s Nature has an article by Geoff Brumfiel with more details on the plagiarism scandal described here. At last count it involves 15 authors, 67 papers on the arXiv, of which about 35 were refereed and published, in 18 different journals. The arXiv has set up a special page with information about this. As far as I can tell from checking a few examples, most of the published papers are still available online at the journals, with no indication of their plagiarized nature. One exception is the plagiarized paper at JHEP, which has now been removed, with the notation
This paper has been removed because of plagiarism. We regret that the paper was published.
As far as I know, neither JHEP nor any of the journals has given any indication of an intent to change their refereeing procedures because of this scandal.
Journal of K-theory
The editors of the new Journal of K-theory have issued a public statement, explaining in detail their plans for how to handle papers submitted to the older journal, K-theory, where they had resigned as editors.