The article in question is Roberta Smith's glowing review of the MoMA's new exhibit Abstract Expressionist New York. The photos show visitors admiring the Krasner, Pollock and de Kooning's on display in the exhibit, however the recently appended editor's note explains:
"The people shown were museum staff members, who were asked by museum officials to be present in the galleries to provide scale and context for the photographs. Such staging of news pictures violates The Times's standards and the photographs should not have been published."
It remains unclear, however, whether it was the staff at MoMA or the Times photographer, Fred R. Conrad, who decided to stage the photos.