This is my second course about Machine Learning (I'm a senior developer with a mathematical background) and I am delighted. This course is probably the best online ML course you can find. Professor John Paisley is an amazing and brilliant teacher ; he doesn't only have the knowledge, he has the talent of teaching, of transmitting knowledge with detail and precision, of explaining, reexplaining, illustrating sometimes complex concepts to make them simpler to understand and digest. I would like to thank him warmly, because my linear algebra and math background were pretty rusted, but it was a so-interesting 3 months, challenging for some parts but at the end of the day, it open perspectives, it provides extra tools of knowledge, it gives you keys of understanding. What a pleasure.
About the content itself, some may think the content is very advanced or complex, while people more familiar with the topic may argue it's just an introduction. Like an other person reviewing the course, I would warn people that it's heavy on mathematics (linear algebra, calculus). If you're familiar with it, just move forward and take this course.
Last thing, lots of people are complaining about Vocareum. I didn't have any problem with it. Just have to wait that your files are saved before submitting them to grading (my first submission was empty because of that, the problem never happened again when I cared about it).