It is starting again on September 17, 2017 though you can access some of the material already.[1] In addition to the quality of the content, one of the most amazing things about previous offerings is just how involved he has been in the forums, directly helping students.
[1] https://www.edx.org/course/learning-data-introductory-machin...
The Ng class was a good introduction, but it was mostly applications, not the mathematics and theory behind them.
[0] https://work.caltech.edu/telecourse.html