The errors identified in the Wikipedia articles selected for last month's review published in Nature have all been addressed. The final corrections needed were made last week, according to Violetriga, one of the participants in a project responding to the study.
The original report, published 14 December 2005 (see archived story), covered 42 articles on scientific topics, comparing the number of mistakes in both Wikipedia and Encyclopædia Britannica. 42 days later on 25 January, the effort on Wikipedia's part to address these errors was declared complete. Only 38 articles actually required changes, however, since Nature reviewers identified no errors in four of them.
Although Nature published the results of the study on 14 December, a detailed report of what errors were found was not initially available. More than a week later, supplementary information (PDF file) explaining the review process in greater detail and indicating the errors identified was posted on the journal's blog.
By this time, work was already underway to address the criticisms, as the articles with problems were tagged with Template:NatureDispute and most began being edited fairly heavily. As a case in point, Cambrian explosion, one of the more flawed articles at 11 errors, had already been the subject of a significant rewrite by Dragons flight. Based on a table used to keep track of progress at correcting the articles, at least 15 mistakes were already fixed before Nature was able to release information about the nature of the errors.
In some cases, the issues were partly traceable to difficulties with the information available. For example Dmitri Mendeleev, the article in which the most errors were found (19), had problems with the number of siblings in Mendeleev's family. He was apparently the last of 13 surviving children, or the last of 17 total. Britannica stated 17 without qualification; Wikipedia said 14 at the time, and some other reference sources give this or some other number. The New York Times reported that a book written by reviewer Michael Gordin actually contained the same number that he identified in Wikipedia as being incorrect. His response: "I believe that is a typographical error in my book."
As the two articles with the most errors, Cambrian explosion and Dmitri Mendeleev were also the last to be checked off. And, as is always the case on Wikipedia, work on any of these articles cannot exactly be considered "finished". As to Mendeleev, to cite one instance, Gordin's review called for more information about "his role as an economic thinker, his work on the theory and practice of protectionist trade, his work on agriculture, etc." The fact that Mendeleev worked in these fields is now mentioned, but without much explanation other than a laudatory quote from a Russian historian of science, so more could certainly be added.