Prof David Malan. Teaches CS50 and CS50x for remote learners through edX. In the immortal words of Russ Hanneman “this guy fucks.” https://www.youtube.com/user/cs50tv
This is a great idea and well presented. I often like to see how others implement a particular API and for what purpose, which in turn keeps me developing new ideas.
I agree with some of the comments about effectively being able to play the exam game. That said, some courses I've seen have offered extra credit, and distinction grades, if certain extra work is undertaken which is not simply guessing exam questions multiple times. Such an example is Cryptography by Prof Katz which is part of the Cybersecurity specialisation. You can pass the course by playing the system, but to do well you need to write code to crack crypto systems. Not something everyone is capable of and offers a different perspective on the overall result. I've done several coursera courses and they've landed me some pretty decent jobs. Just depends on how You sell them :-)
just seen this bbc report on the issue http://www.bbc.co.uk/news/business-35231632, apparently its not a ddos, but this is the 2nd day in a row, so pretty significant internal issue. Possible causes? 2016 leap year :-p ?