The course page is timing out for me at the moment so I can't see what it says, but I emailed coursera last week asking about the start date. Their reply was that it was now expected to start in mid-April.
I've been looking forward to this course for a while. It was supposed to start in March, I hope it doesn't get pushed back again.
I've to register, why?
Because the classes are designed for people who want to take various tests, keep score, track progress and participate in discussion. I think downloadable video files are floating somewhere, not sure about lecture notes, etc.