The obvious alternative is the employers, but we already know the limitations of an employer-led model. The here-and-now culture of a Hiring organisation focuses too much on immediate skill requirement, which does no favours to the students' future prospects. Besides, employer-led training is also old hash, not something suitable for an exciting new thing like MOOC. It will take away the key attraction - that of knowing something really new or novel - and may make the whole thing about filling out forms and ticking the boxes, as vocational education often is.
The less obvious route, but one that fits the MOOC model better, is possibly to build a community of practice around the platform. It is easier in this case than it sounds: The massive scale of MOOCs is really its strength, and the community already includes a number of decision makers, employers and practitioners. Evolving its own global credential model, based around its own community, is plausible: In fact, if anything, this will upset various national regulators less than if MOOCs purport to give out degrees.
It is indeed something that will play out in coming months. The way I see it, MOOCs are here to stay. If anything, they represent an exciting new innovation in education, and one example where private investment can create a credible alternative. But it is a different game: Falling into the socially mandated degree trap will project MOOCs as the inferior alternative, rather than a different route that they really are.