Here is my review of Jul-Aug 2015 Coursera incarnation of Data Visualization, which is the last course in Data Mining specialization. It is ranked 3.2 out of 5 (poor), while I passed with 100% grade.

Technologies/Material: This course is very different from other heavily mathematical courses in the specialization and rather presents the art of conveying meaning with graphical representation of results. The course discusses how humans perceive information and makes recommendations based on that. Most of the proposed techniques would be intuitively familiar to students.Non-trivial presented techniques are: Focus + Context, Gantt charts, StreamGraphs and stacked Bar chars/Line graphs. The course has relatively little material and no homework.

Instructor/lectures: John Hart is a professor of CS in UIUC. He is academically active with almost 100 publications. There was some sort of renormalization of grades applied, my real score was around 90%.