What's even more (pseudo-)surprising/depressing is that, at least according to this thread and subthread, only 1,000 people completed the first homework, out of the ~150k who signed up.
A commenter suggested that this is reasonable considering the wide net they cast for the course compared to the math pre-requisites, and the normal compsci class dropout rate (which increases for large classes).
YouTube view counts are delayed and not-at-all reliable.
Here you go: http://www.ai-class.com/
They're still working out kinks in the site, and no homework is up yet, but the initial set of lectures (really really basic "what is AI/welcome to the first day of class" type stuff is up), so if you signed up, then sign in and hopefully the site will work for you.