They have blogged about it. https://medium.com/digital-moma/thousands-of-exhausted-things-or-why-we-dedicated-moma-s-collection-data-to-the-public-domain-7e0a7165e99

"This data release includes all of the works that have been both accessioned into MoMA’s collection and cataloged in our database. It includes basic data for each work, including title, artist, date made, medium, dimensions, and date acquired by the Museum."

"MoMA’s open data is primarily intended to be useful to scholars, so it was important to make each version citable." 

"Thanks to the Cooper-Hewitt and Tate for paving the way by releasing their own collection data on GitHub using CC0. Thanks also to George Oates (@goodformand) for reassuring us that a CSV is not just the easiest way to start but probably the most accessible format for a broad audience of researchers, artists, and designers."

They actually produced a live, on-site performance about the data released, and blogged about it: https://medium.com/@blprnt/a-sort-of-joy-1d9d5ff02ac9

"This release of open data by MoMA is by no means revolutionary. Two years ago the Tate Modern released its own collection on GitHub. The Rijksmuseum in Amsterdam has not only released its data (images and all), it has also built an API to allow anyone easy access to it. In 2013 the British Museum released 1,000,000 images under a Creative Commons license."

Anyway, this might not be big or surprising news to those of you following closely this scene. I just found amusing to learn accidentally about this the day that Wiki Loves Open Data has started taking shape in a wiki page.