Here is a link to a post from the TopRank website by Dave Folkens. A brief extract:
” At a minimum, this should be on the radar for any business that cares about how its brand is viewed. In the Harvard Business Review study mentioned earlier, a stunning 75% of the companies in the survey said they did not know where their most valuable customers were talking about them. Twitter is a real-time opportunity to listen in on the conversations of 200 million users. Setting up simple searches allows companies to hear comments that could go unnoticed if ignoring this social channel”.