I think your comment is an example of the point of view that the author was talking about. The Google Prediction API won't automate the process of grouping comments or stories by content. Someone has to do the work of collecting the data and preparing the corpus, determining the best way to analyze it and prepping the inputs and outputs. There are levels of understanding and effort between having an idea involving machine learning and getting accurate predictions.

The google prediction api takes care of the code for algorithmic computation. While that's handy, it's only one step of a much larger process. The scale of that process is something that many people don't fully understanding about machine learning (yet).