Free course, but a grade? A certificate?

I got it from DIY Scholar and she has it from Lifehacker:

We have been reporting about many courses that great universities offer for free, whether on audio or video. So what is new about Stanford's newest free course Artificial Intelligence: you can sign up, do the course and get a grade and a certificate. Consider the challenge? The professors, Sebastian Thrun and Peter Norvig, reckon you will have to spend about 10 hours a week to pass, so it may be free, it is not for nothing. Sign up before Sept 10th and you are in.

Apart from the question whether to sign up, I am intrigued by this initiative. Is this where we are going? How many people will sign up? How many will pass? I am sure there will be many more to sign up than Stanford had ever expected. That is how these things go and I am contributing here with the message going viral. But when all is said and done, will it still be more? And how will the average level turn out to be? That may also be more than expected - my hunch.

Either Stanford will find out the bite was way too big to chew, or this is revolution.