"Software as a Service" is an architecture paradigm: little of it is Rails or even web specific. In fact, any competent software developer should be able to get the gist of Rails, Django or flavor of the month framework in the proverbial weekend.
The online course doesn't take months/years, so the nitty gritty of Rails is neither taught, nor is it a requisite for the course: in complete agreement with my position.
There is one that teaches Django?