And then there's the question of what kind of teaching excellence is needed for online learning. So far, universities that have sought an online presence have tended to put their best lecturers online -- the people with the most dynamic personal presences. The Richard Feynman model, the funny, charismatic master explainer, seems to be the thing sought for -- but what if people don't actually learn all that much from such figures?

Consider the distinguished physicist from Harvard, Eric Mazur, who has recently discovered that his students haven't been learning all that much from him and have tended to forget most of what they do learn soon after learning it. He's completely rethinking his teaching style from the ground up, and while his students are now learning more, they're not learning it by watching the kind of show that Feynman once put on.

So: let's go back to Stephen Gordon's hypothetical manager who's trying to decide whether to hire the local college grad or the person with the MITx certificate. Right now that manager is in the dark, because the MITx certificate is an unknown quantity. But a few years down the line some data will be in, and if the MITx certificate holders are able to hold their own, or outdo the local college grads, that will not be because they have watched a bunch of stimulating lectures from world-class scholars, but because people at MIT will have figured out how to design online environments that will maximize learning and retention.

That's going to be the key to the future of online learning: not whether universities simply film their best lecturers, or place all their course materials online, but whether they find an optimal design for online learning.

But of course, as I suggested in my earlier post, it may not be universities who first figure this out: it may be educational entrepreneurs like Sebastian Thrun. If so -- and depending on what kinds of intellectual property claims people like Thrun can make and sustain -- universities may find themselves playing a futile game of catch-up.

The ones best placed to avoid such an unfortunate turn of events are, of course, the wealthiest universities, and if they are willing to invest a lot of money, time, and energy, then they may well end up, as McArdle suggested in her post, ruling the roost even more confidently than they do now. But I'm not yet convinced that many of our most prestigious institutions are in this particular game to win it.

Image: Reuters.

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