Planning has always been the profession of counting things, mapping things, and then trying to develop a coherent rationale for the observed structure of cities and communities. Formal outreach procedures have been carried out for years, ranging from William Whyte's observations of human urban interaction to patterning and zoning of activities and uses on maps. These kinds of studies are rigorous and time-consuming.
With the emergence of the internet and vast networks of computers, cell phones, tablets and social media sites, entire new areas of information gathering about peoples' behavior, as well as their specific input, have come into being. The use of information captured in data streams from many inputs is called Crowdsourcing, and it begins to provide information on a much larger scale, which means more data to look at.
It's also controversial because the information is not from specific, documented, identifiable studies. This creates an issue with planning exercises and data collection because it is not based upon accurate recording of information, it's a compilation of fairly random inputs and thoughts. It begins to resemble a "tag cloud" such as the word cloud captured above from this blog on wordle.net. This Planetizen article discusses some of the impacts of this change on the profession's methodologies.
A very interesting exercise in this application in planning is being carried out by Interface Studio for Master Planning surveys using digital public input. One has to question, however, the lack of control of the online input. Pretty much anyone can crank a comment in there from anywhere. Probably not a lot of people would take the time to fill in a lot of nonsense, however. People with agendas can really slant the information, as opposed to observations and controlled interviews. The validity of this approach will have to be tested against the accepted practices of gathering information in public meetings and surveys before it becomes accepted practice in planning.