After looking at the title of the article and the content, I am starting to believe that there is an ongoing effort to malign the call-centre profession. Though the content of the article has more points supporting the profession than those opposing it, the title carries the view of the only opposing post on it.
As far as the points raised by Sameer, 1. cellphones need to be turned off and you cannot move out of your desk. How many people do you find in the customer facing service sectors ( like private bank cashier, employees at airlines ticket booking counter, boarding pass issuing counter ), who are free using their cellphones and rest-rooms at their wish. As rightly pointed out by Umesh, it's just the nature of the job.
2. Pay is in-sufficient. In any industry, the pay is going to be dictated by demand vs supply equations. If the demand in software job is huge and you think you fit in there more than the call-center job, it's a personal decision to quit call-center and take up a software profession, it's a personal choice. Does not mean that call-centers pay less.