I think there was a sense that the impact was being lost because the audience was so familiar with the form. You combine that with people's attention spans, which are clearly conditioned to be shorter now, and there's a need to vary the paradigm.
I've often been asked to run for office. I have no desire to do that, I would not want my time with the family or the company restricted because of the demands of an elected position.
After trying Atkins and doing Nutrisystem a few times, now I'm just focused on maintaining a healthy lifestyle rather than dieting.