The work on the Open Badge Infrastructure is only slightly encouraging with regard to this challenge.
However, we can’t credential (responsibly) without assessments, and in the midst of all the excitement about badges I’ve yet to hear of any novel (or even uninteresting) work on the underlying assessments themselves
Given the OAR acronym, users of OER are literally up a creek without a paddle. And will be until we start making some progress on the OAR issue.