From the original article- "However, it's worth noting that more than a quarter of the professors felt that their successful MOOC students do deserve credit. Those respondents include faculty members at Penn, Princeton, Duke, and Stanford. Most of them led courses that were oriented to math, science, and engineering." Which makes sense, those are subjects which are probably best suited to this kind of approach.
I've taken a number of MOOCs, from EDx, Coursera, and Udacity. I'm an addict, always in at least one and plan to pretty much permanently keep doing them as long as it's possible to do so.
The 6.002x from EDx was probably the most rigorous of the ones I've done, and I felt a solid sense of accomplishment when it was over. But I don't think I should be awarded MIT credit for it, mostly due to the limited substitutions for lab work.
In fact, I don't think college credit would be appropriate for any of the classes I've done. However, the certificates for most of them do have meaning, and should be taken by employers as a sign that someone is likely to have some competency in the area.
Yes, cheating is possible, so it's not automatic, but you should always be evaluating someone's actual skills that matter to you anyway. An A in a class on their college transcript also doesn't guarantee mastery in any way whatsoever. It's just an indicator that the person may have such.