Google's John Mueller announced on Google+ that the Google PageSpeed Insights API, which has been around since October 2013, has received a bit of an update yesterday.
The update, according to John, gives you "more information about speed & score," it also provides a "clearer format for text-responses." The release notes don't really provide more context on what is new either:
v2 of the PageSpeed Insights API was released in January 2015. It adds support for rule groups, such as 'SPEED' or 'USABILITY'.
John did share the output, where you can see the score for both speed and usability:
For those who manage lots of web pages or many sites, this API would come in handy showing you what pages have problems to potentially fix.
Forum discussion at Google+.