The difference between a fad and a movement is that a movement produces long term enduring change. A fad, on the other hand, feeds off something that already exists: a cultural awareness, a disenchantment, or even a novel idea and expands on it. Through media, publishing, and viral exchange, it becomes a sensation that sells books, creates a lot of activity, makes people feel something exciting—but in the end it doesn't produce enough substance to sustain lasting change in history.
Often, in the midst of something new, we can not tell the difference. Whether it is a fad or a movement won't be known for many years. I am sure many thought John Wesley and what was derisively called "Methodism" was just a fad. It turned out to change the landscape of protestant Christianity (especially in North America) for all time. Anyone who is an evangelical lives beneath its shadow to this day.
In the last 10 to 15 years there have been a few tidal waves of reaction to North American evangelical Christianity: ...1