MIT announced it will offer certificates to students who take their online courses but are not enrolled or admitted to MIT. The credential will be from MITx, not MIT, and it looks like students will pay to receive the credential.
Higher education is an ecosystem of educational content, interaction with instructors/experts, interactions with students, credentials, and accreditation (and likely more that I am not thinking of at the moment). Until all of those aspects are addressed, open education will not overtake traditional higher education (both online and on-campus). With this move, MIT is addressing credentials. In a few years, I would not surprised to see other institutions accept MITx credentials as for-credit courses. Which would bring some form of accreditation, albeit secondarily.